Drone strikes in southern Yemen killed five suspected al Qaeda militants, the country's interior ministry said Friday, as fighting between rebels and ultraconservative Sunnis raged on in the north.

Two strikes killed the suspects Thursday in Abyan province, while a third left no casualties, the ministry said.

The statement didn't say whether the drones belonged to Yemeni or American forces.

Al Qaeda in the Arabian Peninsula, which is based in Yemen, is considered by the U.S. to be the most dangerous offshoot of the terror organization in the world.

Yemen's military waged a wide offensive against the group last year, driving militants out of their strongholds in southern Yemen. Since then, the group has carried retaliatory attacks and the U.S. has launched dozens of drone strikes targeting suspected members.

Yemeni President Abed Rabbo Mansour Hadi faces multiple challenges after the ouster of longtime President Ali Abdullah Saleh, who stepped down after year-long protests. While struggling with al Qaeda in the south and a southern separatist movement, the government also faces turmoil in its restive northern region.

Security officials said Friday that sectarian clashes between rebels and ultraconservative Sunnis killed two people in recent fighting, the latest deaths in ongoing clashes that left dozens dead over the past 10 days.

Shiite rebels known as Hawthis have been fighting ultraconservative Salafis and jihadists in the city of Damaj in the northern Saada province. Security officials said Friday that 12 people also were injured in the last two days.

The officials spoke on condition of anonymity because they were not authorized to brief the media.

Serour al-Wadie, a spokesman of the Salafi movement, said Hawthis used mortars and rocket-propelled grenades in an attack Friday on a mosque in Damaj.

Earlier this week, Hadi warned of sectarian strife and urged both sides to stop the violence in remarks aired on state television.