SANAA, Yemen — A suspected U.S. drone killed three alleged al-Qaida fighters in an airstrike in the central Shabwa province, Yemeni security officials said Monday.

The officials said the overnight attack hit the men's vehicle as they were travelling near the town of Haban.

The officials also said that in the onetime al-Qaida stronghold of Mukalla, on Yemen's southern coast, troops from the United Arab Emirates and others in the Saudi-led coalition who are primarily fighting Yemen's anti-government Shiite rebels conducted raids on homes seeking al-Qaida operatives.

They say some 150 suspects were detained. Activists close to al-Qaida said the men were being tortured in prisons run by Emirati forces. The officials spoke on condition of anonymity because they were not authorized to talk to reporters, while activists did so for fear of reprisals.

Also Monday, the UAE said a pilot and co-pilot were killed in a military helicopter crash, following a similar crash the day before that also killed two Emirati pilots. The statement, carried on the official WAM news agency, said the two UAE Armed Forces pilots had been taking part in the Saudi-led intervention in Yemen.

The statement did not say where the helicopter crashed or offer any details on the type of helicopter involved.

A day earlier, the UAE had announced that an Emirati pilot and co-pilot died "during a routine flight over international waters." A statement on the Saudi Press Agency later said the two were part of the coalition fighting in Yemen.

In May, a UAE military air crash over water killed two on board during a training exercise.