SANAA, Yemen -- Yemeni forces loyal to the internationally recognized government killed 25 al-Qaida militants in heavy clashes Saturday in southern Yemen, a provincial official said, following an airstrike campaign this month by a Saudi-led coalition against al-Qaida positions in the area.

Ground troops were advancing in Saturday's clashes in the town of Koud in the southern province of Abyan, said al-Khedr al-Seidy, the province's governor.

Elsewhere, a suicide bomber detonated a car bomb southwest of the Abyan provincial capital of Zinjibar to stall advances by the military in the province. The explosion led to an unknown number of casualties among the army forces.

Al-Qaida's affiliate in Yemen, viewed by Washington as the group's most dangerous offshoot, has exploited the conflict between Shiite rebels and government forces to expand its footprint.

A Saudi-led, U.S.-backed coalition supporting Yemen's internationally recognized government is battling Shiite rebels known as Houthis and their allies.

The Houthis have held Yemen's capital, Sanaa, since September 2014, and their advance across the Arab world's poorest country brought the Saudi-led coalition into the war in March 2015.

In the central city of Taiz, five civilians were killed and seven others injured when a land-mine exploded as a bus was passing by on a side street west of the city.

Taiz has been besieged for months by Houthis who have been indiscriminately shelling the war-devastated city and blocking the delivery of humanitarian aid, according to residents and aid groups.

Clashes also continued Saturday in the provinces of Marib and Jouf, while the Saudi-led coalition launched airstrikes against the Houthis in Taiz and Jawf.

In over a year since the Saudi intervention, the war has killed nearly 9,000 people -- a third of them civilians, according to the U.N.

The officials spoke on condition of anonymity because they were not authorized to speak to the press.