Two air strikes that targeted two vehicles in south Yemen on Saturday killed seven suspected members of Al-Qaeda and wounded two more, a local official said.

The deaths came on the same day that suspected members of the extremist group shot dead a senior air force officer, and an explosion killed a top police officer.

Saturday's attacks by the Yemeni air force hit the two vehicles on the outskirts of the town of Mahfad in Abyan province, the official said, speaking on condition of anonymity.

The official said Al-Qaeda-linked militants were seen evacuating the casualties and transferring them to a local medical centre.

Al-Qaeda remains active in Mahfad close to Zinjibar and Jaar, which they ruled for a year before being driven out by a government offensive mounted in May last year.

US drones frequently conduct strikes targeting suspected militants as part of Washington's war on the jihadist network across several countries, and in support of Yemen's war on extremists.

Unidentified assailants on Saturday shot dead a senior air force officer in the eastern province of Hadramawt, another area of operations for Al-Qaeda in the Arabian Peninsula (AQAP).

The gunman sped off on the back of a motorbike after killing Colonel Yahya al-Umayssi, commander of the air force detachment in the town of Seiyun, in the inland north of the province, an official said.

A witness said that both assailants were masked but that the gunman removed his mask before opening fire, saying: "In the name of God, Allah is great," as he did so.

Also in Seiyun, an explosive device planted in the car of a senior officer killed him and wounded two of his bodyguards, a security official said.

Colonel Abdulrahman Bashkel, the head of criminal investigation in the Wadi Hadramawt region, died in hospital shortly after the explosion ripped through his vehicle on Saturday, the official said.

Al-Qaeda loyalists had distributed pamphlets and plastered posters threatening attacks against the local CID.

There was no immediate claim of responsibility for the attack, but Al-Qaeda loyalists have carried out a spate of assassinations of security officers in south and east Yemen in retaliation for a US-backed crackdown on its network.

Some 70 security officers have been killed in the region in the past two years in attacks attributed to Al-Qaeda, officials say.

Al-Qaeda exploited a weakening of central government control during the 2011 uprising that forced veteran strongman Ali Abdullah Saleh from power to seize large swathes of the south and east.

AQAP, which is based in Yemen, is considered by the United States to be the most dangerous branch of the global extremist network.