A car bombing killed three government soldiers and injured five others in southern Yemen on Tuesday, according to a local military source.

Axar.az reports that a bomber detonated his explosives-laden vehicle at a gathering of soldiers in Gaheen district in Abyan province, the source said anonymously because he was unauthorized to speak to media.

Eyewitnesses said heavy gunfire followed the explosion.

Flames of smoke were seen rising from the area following the attack, for which no group has yet claimed responsibility.

Yemeni President Abd Rabbuh Mansour Hadi has earlier ordered the deployment of extra forces in Abyan to hunt down al-Qaeda militants, who use rural areas in the province to launch attacks against government troops.

Impoverished Yemen fell into civil war in 2014, when Houthi rebels overran much of the country, including the capital Sanaa.

The conflict escalated when Saudi Arabia and its Arab allies launched a massive air campaign in 2015 aimed at reversing Houthi military gains and shoring up Yemen’s embattled government.

Over 3 million people have fled their homes since the onset of the conflict, and more than 20 million throughout the country are in need of humanitarian assistance, according to the International Committee of the Red Cross (ICRC).