MOSUL, Iraq (AP) -- The Iraqi government on Sunday sent truckloads of food, heating oil and drinking water to residents of areas retaken from the Islamic State group in and around the northern city of Mosul as more civilians streamed out of the city amid intense fighting between the militants and troops.

Diaa Sallal, the top relief official at the Ministry of Immigration and Displaced, told The Associated Press that the supplies were being delivered to the towns of Bartella and Qayara, east and south of Mosul respectively, as well as the outlying Mosul neighborhoods of Ekhaa First and Ekhaa Second.

Sallal, reached by telephone in Iraq's northern Kurdish region, gave no further details.

The government launched a campaign to retake Mosul from IS in October. The fighting has caused shortages of vital supplies like clean drinking water, according to the U.N. and Iraqi officials.

On Sunday, heavy fighting flared up in the eastern sector of Mosul, with both sides exchanging heavy gunfire from rooftops in the Shaimaa neighborhood. IS militants, meanwhile, shelled the district with a heavy barrage of mortars, according to an AP team that witnessed the battle.

Scores of families braved the fighting, leaving their homes and fleeing IS-held districts for the relative safety of the Shaimaa and Entissar neighborhoods, both retaken by government troops, or camps for the displaced at a safe distance outside the city. 

Hamdan al-Abed, an 18-year-old Shaimaa resident, broke down in tears at the sight of members of the Iraqi special forces in his neighborhood and later recounted the brutality of the group in Mosul, which was captured by the militants in June 2014.

"We couldn't resist them, we didn't have weapons and they would kill anyone against them,'' he told the AP. "When the security forces approached our neighborhood, all the Daesh fighters fled with their families deeper inside Mosul,'' he said, using an Arab acronym for the group.

Fighting in Mosul has been mostly focused in the part of the city east of the Tigris River, with the special forces deployed there progressing slowly due to the spirited resistance of IS and fears over the safety of civilians. There are an estimated 1 million civilians inside the city, Iraq's second largest and the last major urban center still held by IS in Iraq.