This is a timeline of the war in Donbas for the year 2015.
January–March 2 January: Ukrainian analyst Dmitry Tymchuk reported single tank incursions around Trokhizbenka, a tactic the rebels used previously against Donetsk airport and dubbed "roaming tank". According to him, single pro-Russian tanks supported by scouts and mortar fire to suppress antitank weapons shoot three or four rounds on a target before shifting its firing positions in order to attack the objective repeatedly. 3 January: Pro-Russian scouts in snow camouflage suits executed harassing fire on Ukraine's 92nd brigade positions near Shchastia using automatic weapons and rocket propelled grenades. 4 January: Heavy shelling was witnessed by local residents in Donetsk city, where militias entrenched around the train station fired "Gvozdika" howitzer salvos on the airport. "Uragan" or "Smerch" artillery rockets were launched from Shchehlovskoho cemetery. Fourteen civilians were injured. 6 January: Heavy shelling was reported at Donetsk airport and other Ukrainian positions. The rebels fired mortars, artillery and multiple-rocket launchers. Ukrainian troops clashed with enemy scouts near Starolaspa, killing two militiamen and scattering the survivors. Some Ukrainian army units attended local churches in the front to celebrate Orthodox Christmas. 7 January: On Christmas Day, Donetsk airport and surrounding locations were once again shelled with mortars and multiple rocket launchers. 9 January: Heavy fighting erupted near Stanytsia Luhanska between the Ukrainian National Guard and rebel militias. Two guards were killed and eight wounded in the clashes, which lasted for two hours. The militias fired "Grad" rockets in the aftermath. According to Luhansk Oblast Governor Hennadiy Moskal, Krymske was struck by mortar fire and "Grad" rockets, while Shchastia became the target of mortars and artillery. Ukrainian and pro-Russian forces trade intense gunfire in the area of Stanytsia Luhanska. 11 January: Two industrial plants were damaged by artillery fire in Donetsk city and in nearby Avdiivka. In Donetsk, 364 workers were trapped inside "Zasyatko" coal mine after a shell hit a power substation, disabling four boilers and 63 transformers. Meanwhile, Avdiivka Coke Plant was repeatedly struck by artillery rounds that affected the fourth and the sixth floors of the main building and the coke and hydrodesulfurization compounds. 13 January: Volnovakha bus attack. At least 13 civilians were killed and 15 injured, after a "Grad" artillery rocket exploded near passenger bus at Buhas roadblock near Volnovakha. Initially separatists took responsibility for this incident, which they thought was a successful destruction of the Ukrainian roadblock. After the information about civilian bus hit the news, they denied having "even technical possibilities" to shell that area. OSCE experts inspecting the place of incident confirmed that it was caused by "rockets fired from a north-north-eastern direction". which coincides with the earlier analyses pointed to Dokuchaevsk as the shelling origin (the actual launching process was also allegedly filmed by local residents). 15 January: The rebels launched a major assault on Donetsk airport, killing two Ukrainian paratroopers and wounding seven, according to Ukrainian sources. The Ukrainian forces had lost by then two thirds of the new terminal. The pro-Russian offensive in the area continued into the next day. One Ukrainian paratrooper was killed and eleven wounded. The rebels launched tear gas grenades to support their assault. 17 January: Shelling of the Donetsk Airport area by separatists significantly increased and as result of a significant push forward their forces effectively surrounded the government forces, cutting supply and enforcement lines. The situation was described as "critical". Communication lines with government forces were also reportedly cut by Russian electronic warfare units operating in the area. In response, Ukrainian forces began a counter-offensive with a number of tanks entering suburbs of Donetsk during the night and morning of 18 January. 18 January: Two Ukrainian soldiers and two civilian were killed in the northern front when Cossack units of the "Great Don Army" fired "Grad" artillery rockets on Trokhizbenka, Shchastia and Popasna. Over the day heavy fighting continued in the airport area and Debaltseve pocket. "Grad" shelling by separatists from Horlivka aimed at Debaltseve was confirmed by OSCE observers based on unexploded ordnances remains. The shelling covered area of 1 km2 and resulted in the death of three civilians and 12 wounded. The mission also observed buildings destroyed by incoming artillery fire in Donetsk and Luhansk, but was unable to establish shelling direction. 19 January: One Ukrainian "cyborg" — the nickname of the Ukrainian paratroopers defending Donetsk airport — was killed and ten wounded during the renewed rebel offensive on the new terminal, where the roof of the second floor collapsed after being blown up by the separatists. The rebel militias stormed the ground and second floors of the new terminal building. Ukrainian troops continued to hold out on the first floor of the building until the separatists blew up the second floor, causing it to collapse onto them. Several soldiers were killed or trapped in the rubble. Pro-Russian forces supported by tanks and artillery launched a large offensive on Bakhmutka road, taking over checkpoint No. 31, north of Frunze, and threatening checkpoint nº 29 to the west. The main objective of the rebel operation was to isolate Krimsky. The village of Zholobok was overrun by what the Ukrainian forces described as "Russian troops". At least two Ukrainian soldiers died in the assault, according to commander Semen Semenchenko. Ukrainian officials and soldiers on the ground insisted that the attack was carried out "not by separatists or Cossacks, but by Russians". 21 January: The Ukrainian army acknowledged that their forces withdrew from the old and the new terminals of Donetsk airport, but kept control of the airfield and its surroundings. Six Ukrainian paratroopers were killed during the rebel assault, and another 16 were taken prisoner. An OSCE report said that 80 Ukrainian defenders of the airport, treated at a hospital in Konstyantynivka, showed symptoms compatible with a poison gas attack, such as convulsions, vomiting, dyspnea and loss of consciousness. 22 January: Ukrainian President Petro Poroshenko announced that the Ukrainian armoured forces had prevailed in what he described as "tank battles". Poroshenko claimed that three rebel tanks and two trucks loaded with ammunition were destroyed, and several armoured personnel carriers and fighting vehicles captured. The Ukrainian military had reported a "tank duel" near the village of Krimsky at 10 a.m. Earlier, Semen Semenchenko said that members of the Ukrainian 24th Mechanized Brigade knocked down at least three enemy tanks on Bakhmutka road, in the area of checkpoint nº 31. Another tank was disabled by a recoilless rifle while attempting to overrun checkpoint nº 29. Further efforts to surround the Ukrainian position were hampered by the icy roads. The nearby village of Toshkivka was hit by artillery fire from Stankhanov. 23 January: Intense fighting continued on Bakhmutka road. Ukrainian sources said that checkpoint nº 31, abandoned by Ukrainian troops after the pro-Russian offensive, remained unmanned and under heavy artillery fire from the Ukrainian side. Rebel artillery in the area shelled Krimsky, Trokhizbenka, Novotoshkivka and Nyzhnje. Shchastia, Valuiske and other settlements were attacked with tanks and mortar fire. Anti-aircraft guns were fired on Ukrainian outposts around Krimsky. An assault on Ukrainian positions at Novotoshkivka was beaten off by artillery fire. Sources from the self-proclaimed Donetsk People's Republic claimed that a Ukrainian multiple launched rocket barrage killed 24 pro-Russian troops. 24 January: At least 30 civilians were killed in Mariupol when pro-Russian forces shelled the city with artillery and "Grad" rockets launched from the village of Novoshyrokivske (Oktyabr) (19 km NE) and Zaichenko (15 km NE), according to OSCE reports. 26 January: Heavy fighting continued around Sanzharivka, in Debaltseve pocket, where the pro-Russian forces launched an offensive supported by tanks on 25 January. The main Ukrainian stronghold there was the target of "Grad" rockets on six occasions. Two people was killed in Stanitsya Luhanska after the town was hit by rebel artillery. Most of its inhabitants had been evacuated. In the same area, pro-Russian armoured columns were trying to cross the river Seversky Donets at different points. 28 January: Without power, gas and water supply for the ninth consecutive day, the residents of Debaltseve were on the brink of a humanitarian catastrophe. Six people were killed and 12 wounded over the last 48 hours in Horlivka, as a result of heavy fighting in the area. 28 January: The rebel offensive on Debaltseve pocket continued in full swing. Separatist troops broke into Maloorlivka overnight, but their advance was halted by the Ukrainian defenders. Pro-Russian tanks from Horlivka burst into Uglegorsk early in the morning, meeting Ukrainian forces in the city's centre. Heavy fighting went on into the evening, despite "Azov" battalion's claims that the assault was beaten off and Ukraine's National Guard was "cleaning up" the remaining separatists. 30 January: The rebel offensive on Debaltseve pocket continued. Fierce fighting was underway in Uglegorsk, where Ukrainian authorities acknowledged that the separatists took control of at least some areas of the town. Militiamen on the ground said that the only remaining resistance came from Ukrainian forces entrenched in the local train station. Pro-Russian artillery killed seven civilians at Debaltseve itself. At this point the frontline was just 15 km away. In the area of Bakhmutka road, rebel forces fired on Ukrainian troops around Krimsky and Shchastia with tanks and antitank missiles. Shchastia itself was the target of "Grad" rockets. Krimsky and Hirske were attacked three times using mortars and artillery. 31 January: Over the last three days, Ukrainian forces evacuated 956 people -among them 161 children- from the towns of Debaltseve, Avdiivka and Svitlodarsk. The rescuers moved out 310 civilian residents from Debaltseve alone. Ukrainian media reported that Uglegorsk was "now really in the hands of enemy forces", after an ill-fated Ukrainian counterattack which left four Ukrainian army tanks disabled. The remaining Ukrainian troops withdrew from the town. Separatist shelling killed 12 civilian residents in Debaltseve itself. 1 February: Brigadier general Isa Munayev was killed in a battle around Debaltseve. Donbas Battalion commander Semen Semenchenko was wounded and four of his subordinates killed during an attempt to retake Uglegorsk. Another 11 Ukrainian soldiers were evacuated to a Kharkiv hospital. 3 February: In the area of Bakhmutka road and Stanytsia Luhanska, the militias resorted again to single tank attacks on Ukrainian forward outposts, also known as "roaming tank" tactics. 5 February: Separatist artillery killed five local residents at Debaltseve pocket during the day. In the afternoon, pro-Russian forces fired on Ukrainian positions on 49 occasions in Debaltseve pocket only. Most of the attacks were carried out on Mius, Chernukhin and Troitske. 6 February: In a short lull of fighting in ongoing Battle of Debaltseve, DPR and Ukrainian forces agreed to establish a humanitarian corridor on 6 February, in another attempt to allow the remaining civilians to escape from Debaltseve.