Two soldiers from Yemen's Southern Transitional Council were killed in an ambush on a convoy in the city of Aden on Thursday morning.
A passer-by also died in the attack in Aden's Bouraika district, a security source told The National.
"An explosive device planted in a dumpster on a dirt road in Al Shaab area went off as the convoy of the Backup Forces, a security division set up in Aden in 2017, passed by," the source said
"Two soldiers and a passer-by were killed and 12 soldiers were injured in the explosion, which was followed by extensive gunfire from elements hiding along the road," the source said.
"The blast hit the car carrying the commander of the Backup Forces, Gen Mohsen Al Wali, and his assistant, Gen Nabil Al Mashoshi, who survived the attack."
No group claimed responsibility for the ambush and the government did not offer comment.
The STC forces said on Twitter that the attack was an assassination attempt. Video footage shared by STC activists on Facebook showed a white four-wheel-drive vehicle with extensive damage.
The ambush came a day after security forces in Aden announced new patrols under a plan to strengthen security in the city. Security forces also started taking measures against constructions illegally built during the chaos of the civil war.
Aden is the seat of Yemen's internationally recognised government, which in December formed a new power-sharing Cabinet, including the STC, under a deal brokered by Saudi Arabia.
The Saudis lead a military coalition fighting to oust the Iran-aligned Houthi movement that controls much of north Yemen and the capital, Sanaa, and restore the government of President Abdrabu Mansur Hadi.
On December 30, at least 22 people were killed and dozens wounded in an attack on Aden airport moments after a plane carrying members of the new Cabinet landed. The coalition blamed the Houthi movement, who denied responsibility.
The power-sharing deal ended a stand-off that triggered clashes in Aden and complicated United Nations efforts to broker a permanent ceasefire in the overall conflict.
The war has killed more than 100,000 people and caused the world's largest humanitarian crisis.