GOMA, Congo (AP) -- Neighbors said at least five civilians were hit by mortar fire in the eastern Congo city of Goma on Thursday during a second day of heavy fighting between government forces and M23 rebels to the north of the town.
The violence marked the first reports of civilians being wounded inside the city since late May, and prompted the U.N. peacekeeping mission to issue a statement saying it would take the "necessary steps to protect civilians."
At U.N. headquarters in New York, Assistant Secretary-General for Peacekeeping Edmond Mulet briefed the Security Council on the fighting, which lasted through most of Thursday.
U.N. diplomats said he reported that three people were killed during the fighting.
U.N. peacekeepers responded by firing five mortars and sending attack helicopters to fly over the scene though they didn't fire, the diplomats said, speaking on condition of anonymity because the briefing was private.
Clement Sale said two of his nieces -- ages 16 and 17 -- were wounded, one seriously, when a mortar round fell on their house in a densely populated residential neighborhood of Goma.
Another witness, Dieudonne Kwibuka, told The Associated Press that at least three other people, were wounded by mortar rounds that fell near an Anglican church in the same neighborhood, near the center of the town.
The victims included a 3-year-old and a 6-year-old, and one of them had sustained severe head injuries and was unlikely to live, Kwibuka said.
Residents at both locations said they believed the mortar rounds had been fired by Rwandans.
"We could see and hear the direction they were coming from," said Kwibuka.
Rwanda has consistently denied allegations of involvement in the Congolese conflict or of support for the M23 movement, which is led by veterans of previous rebellions that were backed by Rwanda.
The Rwandan border is about 3 miles (5 kilometers) east of where the mortar rounds landed Thursday, whereas the fighting between the army and M23 was some 8 miles (13 kilometers) to the north.
A statement issued by the U.N. peacekeeping mission in Congo, MONUSCO, said "populated areas and U.N. troop positions have been directly targeted and hit by indiscriminate mortar fire" in the Goma area since Wednesday.
"I have ordered MONUSCO to react and take necessary steps to protect civilians and prevent any advance by the M23," the new head of the mission, Martin Kobler, said in the statement.
Both sides have blamed each other for the resumption of hostilities on Wednesday after a three-week lull.
An M23 spokesman Kabasha Amani accused the army of massing troops in front of rebel positions shortly before the fighting broke out and of firing mortar rounds at a populated village, Kayanja, inside the rebel-held zone.
Army spokesman Colonel Olivier Hamuli said there were no civilians inside the combat zone to the north of Goma.
A civilian living near the combat zone, Dr. Isaac Warwanamiza, said the army was advancing Thursday and the front line had moved nearly a kilometer (more than a half mile) north since Wednesday.
The M23's Kabasha called on the government to return to peace talks at Kampala that have repeatedly stalled since they were launched last December.
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