Sanaa, Yemen (CNN) -- Twin suicide attacks in southern Yemen killed 12 tribesmen early Sunday morning, authorities said. The tribesmen are part of a small force fighting al Qaeda-affiliated militants in Abyan province . In one of the attacks, a suicide bomber approached a group of fighters, shook hands and sat with them before detonating explosives, tribal fighters said. The blast killed five people, in addition to the bomber. In the second attack, seven people were killed in addition to the suicide bomber, the fighters said. Clashes in Abyan have been ongoing since May, when suspected al Qaeda militants took over the province and declared it an Islamic emirate. The militants call themselves "Ansar Sharia," and say that their mission is to spread Islamic law in Yemen. Government forces, with the help of local tribal fighters, have succeeded in retaking control of parts of the province.
The tribesmen are part of a small force fighting al Qaeda . In one of the attacks, a suicide bomber shakes hands with the fighters before detonating . Clashes in the province have been ongoing since May .