Armed men have launched simultaneous attacks on the intelligence and security services building in Yemen's south, killing security officials, witnesses say.

They spoke of "dead and wounded" in the attack, which occurred in Zinjibar, a town in the southern province of Abyan, at 8am (0500 GMT) local time on Wednesday.

Other sources told Al Jazeera that at least two people along with three of the attackers had been killed and seven people arrested.

Mohammed al-Qadhi, a journalist in Sanaa, Yemen's capital, said: "We have information that armed people have attacked intelligence buildings and they have killed some security people - maybe two or more.

"We do not have clear information about exactly what happened, whether it is al-Qaeda or other armed groups. The government is facing [resistance] from a separatist movement in the south of Yemeni, so it it's not clear."

The attackers were armed with rocket-propelled grenades, assault rifles and grenades, one witness said.

Police are blaming al-Qaeda operatives in the region for the assault.

Hakim al-Masmari, editor-in-chief of the Yemen Post, told Al Jazeera: "Our sources confirm that the attack was from al-Qaeda ... I think al-Qaeda is trying to make a strong presence in the south to make the Yemeni government having the idea of a separation less practical."