U.N. combat brigade fires on Congo rebel positions GOMA, Democratic Republic of Congo (Reuters) - A new U.N. combat brigade formed to try to neutralize armed groups in Congo by force if needed fired artillery at M23 rebels menacing the eastern border city of Goma anew, U.N. and Congolese military officers said on Friday. It was the brigade's first clash with M23 in support of government forces in the Democratic Republic of the Congo. The U.N. force, composed of Tanzanian, South African and Malawian soldiers, was created by the U.N. Security Council in March. Fighting entered a third successive day near Goma, a city of about a million people on the Rwandan border, after a relative lull in the 18-month-old M23 rebellion. Goma was briefly seized by the M23 last year and the United Nations pledged in July to prevent the rebels from getting back within range of the city. But the rebels this week entered a security zone ringing Goma that had been established by the robustly-mandated U.N. Intervention Brigade earlier this month, and at least two people were killed when three shells landed in the city center. U.N. Lieutenant-Colonel Felix Basse said another M23 shell crashed near Munigi on Goma's outskirts, where a U.N. peacekeepers' base is located, causing some civilian casualties. Of course we responded with artillery, as we cannot accept any threat to the population. That's why we retaliated," he told Reuters by telephone from Goma. Clashes between M23 and the Congolese army continued early on Friday with government forces repelling two rebel assaults, according to Colonel Olivier Hamuli, spokesman for the Congolese army, known as FARDC. "The (U.N.) brigade is engaged on our side, they're supporting us with their artillery," he said. Basse could not confirm further brigade involvement in Friday's fighting. An M23 spokesman did not confirm on Friday that they had been fired on by U.N. peacekeeping troops and said the group was trying to avoid direct clashes with them. It's not just the brigade we're trying to avoid fighting but the FARDC too ... If the army carries on attacking us we're going to defend ourselves," Amani Kabash said. The army has got tanks and helicopters and they haven't pushed us back at all. That's why they're crying for MONUSCO to help. A South African military spokesman said the country's troops in Congo had not clashed with M23. The fight is taking place near where our troops are positioned. We have a defensive line but we have not engaged," Siphiwe Dlamini said. Additional reporting by Jonny Hogg in Kinshasa and Jon Herskovitz in Johannesburg; Writing by Bate Felix; Editing by Mark Heinrich This story was refiled to amend byline