MOGADISHU (Reuters) - Somali government troops and opposition supporters - including some soldiers - exchanged gunfire in Mogadishu on Friday in street clashes that broke out during a protest march over delayed elections. Demonstrators said they had been attacked first by the government forces. Residents reported sporadic shooting and said rocket-propelled grenades had also been fired. The violence, which followed fighting overnight, subsided by Friday afternoon. But it fueled concern that the military could split along clan lines. It could also strengthen an al Qaeda-linked insurgency, especially as hundreds of U.S. troops have just pulled out of Somalia. Lawmakers were due to select a new president on Feb. 8, but the process was delayed after the opposition accused President Mohamed Abdullahi Mohamed, who is seeking a second term, of packing regional and national electoral boards with supporters. An opposition alliance says his term has expired and he is no longer president. Mohamed is from the powerful Darod clan. But most military units in and around the capital are from the Hawiye clan, which is heavily represented in the opposition alliance. In Friday’s anti-government demonstration, opposition leaders marched with armed bodyguards. Video showed civilians in facemasks - accompanied by friendly soldiers in red berets with ammunition belts wrapped around them - waving Somali flags before scattering when gunfire erupted. “Many forces heavily attacked us, I am now on my chest in an alley,” protester Farah Omar told Reuters by phone. Some soldiers took part in the fighting on the opposition side. Reuters journalists heard intermittent gunfire and heavier explosions. Another video showed flames where a rocket-propelled grenade hit a row of shops opposite the airport entrance. Slideshow ( 4 images ) The Medina hospital told Reuters it had recieved “a few” wounded people, but there was no information on casualties from four other public hospitals. A captain at the military hospital said they had received three dead and 10 wounded from fighting the previous night. The spillover of political rivalries into conflict will dismay Somalia’s allies and play into the hands of the al Qaeda-linked al Shabaab insurgency, which mounts attacks on civilians around East Africa in its bid to impose strict Islamic law. “The military is dissolving and many troops seemingly reverting to clan loyalties,” said Colonel Ahmed Abdullahi Sheikh, who served for three years until 2019 as the commander of Somalia’s U.S.-trained Danab unit. “It’s a mess. There’s no longer any command structure whatsoever.” He said he feared that some troops would leave their bases to join in the fighting in the capital. “This will really empower al Shabab. Over a decade’s worth of gains might be lost,” he told Reuters. The violence comes weeks after the United States pulled hundreds of U.S. troops out of Somalia on the orders of then President Donald Trump. The U.S. forces had largely been supporting Danab. Sheikh said the U.S. presence had also helped shield the force from becoming embroiled in politics, something many soldiers privately feared. Slideshow ( 4 images ) OVERNIGHT ATTACKS Hours before Friday’s demonstration, former president Sheikh Sharif Sheikh Ahmed accused government troops of attacking a hotel where he was staying with another ex-leader. “Farmajo attacked us with armoured vehicles. That is dictatorship,” Ahmed said, using Mohamed’s nickname. “He attacked us and residents at Maida hotel. We ask all civilians to come out and respond.” Security Minister Hassan Hundubey Jimale accused the opposition of starting the fighting. “Armed militia attacked government forces. We repulsed and overpowered the militias,” Jimale said in a statement. Mogadishu resident Ahmed Aden, 44, told Reuters on Friday he had to flee during the night’s gunbattles. “Last night we took our children and mattresses on our shoulders and fled before war started,” he said. “We returned at gunpoint. Turkish-made armoured vehicles and government forces blocked every road and alley.” POLITICS BY OTHER MEANS Somalia has been riven by civil war since 1991, when armed clan warlords overthrew dictator Mohamed Siad Barre then turned on each other. In recent years, internationally-backed efforts have tried to mould militias into national forces under the control of the fledgling federal government, but loyalty to individual commanders and clans remains strong. That means both government and opposition can call on armed supporters if there is further fighting, raising the spectre of rival forces once again battling in the streets of the capital. The stand-off imperils Somalia’s recent history of peaceful transitions, said former national security adviser Hussein Sheikh Ali, who now runs the Mogadishu-based Hiraal Institute thinktank. “Somalia – although known as a failed fragile country – has had some success in terms of power exchanging hands peacefully,” he said. “This is the first time that is under threat.” Residents were angry about the crackdown on protesters, he said, after the city had welcomed Mohamed - an outsider - as president when he was elected.