At least three suspected al-Qaeda militants were killed on Monday in a U.S. drone strike on a car in southeastern Yemen, local residents said, the third such strike in a week.

The attacks show there has been no letup in a U.S. campaign against suspected militants despite a power vacuum left by the resignation of President Abd-Rabbu Mansour Hadi who had publicly backed the program.

The United States regards al-Qaeda in the Arabian Peninsula (AQAP), which has claimed responsibility for last month's deadly attack on France's Charlie Hebdo newspaper in Paris, as one of the most powerful branches of the global militant group.

Yemeni officials said the drone fired two missiles at the vehicle, which was travelling on a dirt road between the town of Maswara in al-Bayda province and the city of Beihan in Shabwa province in southeastern Yemen.

The strike destroyed the vehicles, killing the three people inside it. Residents reported explosions inside the vehicle after the strike, suggesting it was carrying weapons.

The United States has been cooperating with Yemeni security forces to track and kill suspected AQAP members in the country's deserts - a strategy that rights groups have criticized for causing repeated civilian deaths.

But after Shi'ite Muslim rebels overran the capital Sanaa in September and took over President Hadi's residence in January, he and his cabinet resigned.

Hadi was a staunch defender of the drone program, and his exit has left the Shi'ite Muslim Houthi group, whose motto is "death to America", the de facto rulers of the country.

U.S. officials have told Reuters the Houthi takeover was depriving them of sufficient intelligence to locate AQAP targets and avoid killing civilians in the attacks.

On Saturday, a drone struck a vehicle in the remote desert town of al-Saeed in Shabwa, and residents told Reuters the dead men were al Qaeda militants.

The first drone strike since Hadi's resignation came last Monday and killed two suspected AQAP militants and a sixth grader.

Nineteen U.S. drone strikes killed 124 militants and four civilians in Yemen in 2014, according to the New America Foundation, which maintains a database of drone operations.

Reuters