ADEN: An apparent US drone strike killed six suspected Al-Qaeda militants overnight, a Yemeni military source told AFP on Sunday.

The six suspects were travelling in a two-vehicle convoy in Mahfad in the southern province of Abyan, much of which was held by the jihadists before an army counter-offensive last year, the source said, speaking on condition of anonymity.

“A night drone strike targeted two cars of Al-Qaeda militants in Wadi Dhiqa in Mahfad, killing the six people inside them,” the official said.

In a major offensive in summer 2012, the Yemeni army drove Al-Qaeda militants out of most towns in Abyan, including Zinjibar and Jaar which they had held for a year.

But the jihadists retain a presence in the nearby mountains of Mahfad.

Although weakened, Al-Qaeda militants still carry out hit-and-run attacks against members of the security forces.

Al-Qaeda in the Arabian Peninsula took advantage of the weakness of Yemen's central government during an uprising in 2011 against now-ousted president Ali Abdullah Saleh to seize large swathes of territory across the south.

The United States has stepped up its support for Yemen's battle against AQAP, which it regards as the most active and deadliest branch of the worldwide Al-Qaeda network.

US drones strikes in Yemen nearly tripled in 2012 compared to 2011, from 18 to 53, according to the New America Foundation, a Washington-based think tank.

Several AQAP leaders have been killed by US drones, most recently the network's deputy leader Saeed al-Shehri whose death was confirmed by the jihadists on July 17.