An explosion targeting a military ambulance in Yemen's southeastern province of Shabwa killed four soldiers loyal to the country's government on Sunday, a government official told Xinhua.

The local government source, who spoke on condition of anonymity, said the blast occurred when the military ambulance belonging to the Shabwa Defense Forces hit an explosive device while passing through the Musainah area in the eastern part of Shabwa province.

He said that the killed were members of a military medical team inside the ambulance, which was completely destroyed in the blast.

Preliminary investigations indicate the attack was carried out by al-Qaida militants, who maintain a presence in remote parts of Shabwa despite ongoing operations against them by the government forces, according to the official.

Photos and videos circulating on social media showed the ambulance completely destroyed, with wreckage scattered across the area where the explosion happened.

The local Yemeni government forces backed by Saudi Arabia frequently clash with al-Qaida as the militant group tries to take advantage of Yemen's civil war to strengthen its foothold.

This latest attack comes amid ongoing conflict and instability in Yemen. No group has yet claimed responsibility for the explosion.

Yemen has been embroiled in a devastating civil war since 2014, with the Houthis fighting against the internationally-recognized Yemeni government. The Saudi Arabia-led coalition intervened in the conflict in support of the Yemeni government in 2015.