Sanaa, July 11 (RHC)-- A fresh U.S. drone strike has killed at least four suspected al-Qaeda militants in the southern Yemeni city of Mukalla, which was seized by the terrorists in April, Yemeni security sources say.

The unnamed Yemeni officials said that the air raid took place on Friday night in Mukalla, the capital of Hadhramaut province. According to sources, the unmanned aircraft fired several missiles on al-Qaeda militants travelling by car in the coastal city. At least five other militants were injured in the airstrike, they added.

Local residents and witnesses said that the explosion was heard in some parts of the city following the aerial attack.

The United Nations says more than 3,000 Yemenis have been killed and 14,000 more injured in over three months of conflict in the country. Local Yemeni sources, however, say more than 4,500 people have been killed in the ongoing strikes.

In addition to Yemen, Washington has been carrying out drone strikes in several other Muslim countries, including Afghanistan, Pakistan, and Somalia, for more than a decade.