Sanaa , Yemen ( CNN ) -- Four civilians were killed and three were injured Thursday when their vehicle was shelled in Yemen 's southern Shabwa province , two Interior Ministry officials said . Eyewitnesses told CNN that two of the injured are in serious condition . The civilians are part of the powerful Awaliq tribe , which is demanding an explanation from the Yemeni government . Tribal leaders blame government forces from a nearby military base for the mistake attack . `` The shelling came from the direction of a military base , and militants do n't have a presence in those areas , '' a witness said . But a senior military official in Shabwa denied the military had anything to do with the shelling . `` The army is trained and such a mistake is not possible , '' the official said . He blamed terrorists for the attack , saying it was meant to cause friction between the Awaliq tribe and government forces . Government troops have taken control of a number of districts previously held by al Qaeda militants . Thursday 's shelling came nearly a month after Yemen launched a military offensive against al Qaeda in the Arabian Peninsula amid an uptick in violence in the capital . Thousands of troops were deployed to the provinces of Hadramout , Shabwa , al-Baitha and Abyan . Al Qaeda-linked militants killed by Yemeni security forces .
Four men -- members of the powerful Awaliq tribe -- die in clashes in Yemen . Tribal leaders blame Yemeni government forces . The Yemeni government says it was the work of terrorists .