Fourteen inmates, mostly from Al-Qaeda, managed to escape from the central prison in Yemen's capital Thursday when gunmen launched a deadly assault on the facility, officials said.
Seven policemen and three gunmen were killed, according to the interior ministry and security officials.
Another two policemen and two gunmen were wounded, and one of the attackers was captured, the ministry said.
The two-pronged attack began when an explosives-laden vehicle exploded at the facility's eastern entrance shortly after sunset, breeching a hole in the prison fence, security officials said.
At the same time, gunmen attacked guards at the main entrance, creating a diversion that allowed some of the prisoners to escape through the hole in the fence.
One official told AFP that "14, mostly Al-Qaeda inmates" had fled.
Residents said earlier that an explosion and heavy gunfire rang out near the jail, in the capital's north, where officials say around 5,000 prisoners are held, before security reinforcements were dispatched to the area.
In October, security forces foiled an attempt by some 300 Al-Qaeda inmates to escape after they mutinied in another Sanaa prison.
A number of guards and inmates were wounded but none killed .
Nasser al-Wuhayshi, chief of Al-Qaeda in the Arabian Peninsula -- seen by the United States as the network's deadliest franchise -- vowed in August to free imprisoned members of his network.
Wuhayshi himself escaped from the same Sanaa prison with 22 other members of AQAP in February 2006 and was named as the group's leader a year later.
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The AQAP detainees escaped through a 44-metre (145-foot) tunnel they dug between their cell and a nearby mosque.
Thursday's assault was the second major one in the capital in a little over two months.
In early December, a suicide bomber and several gunmen attacked the defence ministry in a brazen operation in broad daylight, killing at least 52 people and wounding another 167.
Thursday's operation came as Saudi Arabia's interior ministry announced that Yemen has handed over 29 Saudis wanted for suspected links to Al-Qaeda.
Eleven of them had already been jailed and later released from prison in Saudi Arabia, Yemen's oil-rich neighbour, ministry spokesman General Mansur al-Turki said.
Nine others were on trial in the kingdom when they fled.
The Yemeni defence ministry had also announced the handover this week without giving details.
Former prisoners at the US prison in Guantanamo Bay, Cuba who had been returned to Saudi Arabia in December 2006 later escaped to Yemen, two years ago after completing a reform programme.
Saudi and Yemeni Al-Qaeda branches merged in January 2009 to form AQAP, posing a serious threat to Western interests across the region.
After a wave of deadly Al-Qaeda attacks in the kingdom between 2003 and 2006, Saudi authorities launched a crackdown on the local branch of the group founded by the late Osama bin Laden, himself Saudi-born.
AQAP has taken advantage of the weakening of the central government in Sanaa since a popular uprising that toppled president Ali Abdullah Saleh in 2011.