The weapons, including new Kalashnikov assault rifles and Chinese versions of them, were stolen by Somali National Army soldiers who had been trained by the UAE at its facility, three Somali men who purchased weapons from the soldiers told Reuters.

The Gulf nation has trained hundreds of Somali troops since 2014 as part of an effort boosted by an African Union military mission to defeat an Islamist insurgency and secure the country for the Somali government, which is backed by Western nations, Turkey and the United Nations.

The UAE ended the programme on April 15, shortly after security forces at Mogadishu’s airport seized millions of dollars and temporarily held a UAE plane.

The escalating diplomatic dispute is one aspect of the fallout in volatile Somalia from a crisis in the Gulf region that has spilled into the Horn of Africa.

Somalia’s relations with the UAE are strained by a dispute between Qatar and Saudi Arabia because Mogadishu has refused to take sides. The UAE and Saudi Arabia have strong trading links with and influence in Somalia, offset by the sway of Qatar and its ally Turkey, one of Somalia’s biggest foreign investors.

Neither Somalia nor the UAE is showing urgent interest in resolving their dispute, said Rob Malley, president of the International Crisis Group, a think-tank.

Somali officials wanted to be seen "standing up” to the UAE, "and the Emirati officials’ position is, ‘If Somalia doesn’t want our money, fine, we’ll take it elsewhere,’” Malley told Reuters in Nairobi after returning from a trip to Mogadishu.

The UAE-trained troops began stealing weapons from the facility shortly after the programme was disbanded, the dealers said. The soldiers sold guns directly to the dealers and indirectly via their brokers.

The looting appears to have occurred while the UAE was in the process of emptying its training centre.

On Sunday night a ship docked at Mogadishu’s port was loaded with equipment from the UAE’s training centre, including several dozen shipping containers of weapons, dozens of armoured vehicles fixed with anti-aircraft guns and hundreds of cars, a port staff member told Reuters.

On Monday, gunfire broke out at the former training centre where some of the troops were still camped out, and UAE-trained troops who were still there fled with as many weapons as they could, before a rival group took over the facility.

Residents in the area told Reuters they saw UAE-trained forces discarding their military uniforms and fleeing the facility in three-wheeled rickshaws with guns in their laps. [L8N1S0508]

After 90 minutes of sporadic gunfire, the facility was secured by presidential palace guards, a Reuters journalist at the scene said.