A US drone killed four suspected Al Qaeda members in an overnight strike as they were travelling through the central desert province of Marib, local officials said on Wednesday.

One said that authorities had not been able to identify those killed because the bodies were so badly burnt.

Marib, now under the control of President Abd-Rabu Mansour Hadi's internationally recognised government, is one of several regions where Al Qaeda in the Arabian Peninsula (AQAP) and its local affiliate, Ansar al-Sharia, operate and is east of the capital Sanaa ─ controlled by the dominant Houthi group.

“A drone hit a car carrying four suspected Al Qaeda members near the town of Al Hami. The vehicle was completely burned and the persons inside were killed,” a second Marib official said.

AQAP has exploited two years of civil war to recruit followers and cement its dominance in the central and southern part of Yemen, where a Saudi-led coalition, with logistical support from the US air force, has been fighting the Houthis to try to restore Hadi to power.

The Houthis seized much of northern Yemen including Sanaa in a series of lightning military operations that began in 2014, eventually forcing Hadi to flee. The Houthis regard their move on Sanaa as a revolution against corruption.

The United States has repeatedly attacked AQAP with aircraft and unmanned drones in what US officials say is a campaign to degrade the group's ability to coordinate attacks abroad.

In late January, at least 30 people were killed in a US commando dawn raid in southern Yemen, including at least 10 women and children, in the first such military operation authorised by President Donald Trump.

The new US administration has not yet laid out a clear policy on drone strikes, but Trump has said he would support an escalation of the fight against Islamist militant groups.

US drone strikes have become more frequent in recent weeks, with at least six reported by Reuters last month.

The previous administration regularly used drones to attack the militant Islamic State (IS) group, Al Qaeda and other militant groups in Syria, Iraq, Pakistan and Afghanistan. Human rights groups criticise the tactic because of civilian casualties.

The Saudi-led coalition has recently made gains against the Houthis in western Yemen but fighting on other fronts, including Marib, has been static, with little ground changing hands.

The coalition accuses Iran of trying to use the Houthis to expand its influence in Yemen, one of the poorest Arab countries. Iran denies this.