Taleban militants attacked the prison with a truck bomb and rockets
Afghan security forces are searching for hundreds of prisoners who escaped a jail in Kandahar, Afghanistan, after Taleban fighters blew up the main gate.
An official in the southern city told the BBC about 350 Taleban militants had got away and 15 guards were killed in the truck bomb and rocket attack.
More than 1,000 people are thought to have escaped, Kandahar provincial council head Wali Karzai said.
Nato troops are helping Afghan forces hunt for the prisoners.
The BBC's Martin Patience, in Kabul, says the Afghan police and army are conducting house to house searches in Kandahar, while Nato forces are using helicopters to secure the city and the outlying districts.
A state of emergency was declared in the city, the second biggest in the country, after the attack on Friday night. All residents were ordered to stay in their homes.
A Taleban spokesman, Qari Yousef Ahmadi, said that 30 fighters on motorbikes and two suicide bombers had attacked the prison, freeing about 400 Taleban members.
A number of high-ranking Taleban field commanders are believed to be among those who escaped.
A state of emergency has been declared in the city
Prison chief Abdul Qabir said some of the inmates had chosen to stay behind during the break-out. They were said to be mostly women, children and political prisoners.
Wali Karzai, head of the Kandahar provincial council and also the brother of the Afghan President Hamid Karzai, suggested that the search for the escapees might prove futile.
"Honestly I don't know because this area you can walk to the other districts. They might recapture some people but I don't know."
An eyewitness told the BBC that the force of the initial blast had been enough to blow out windows up to 3km (1.7 miles) from the prison.
People living nearby also reported hearing blasts from rockets and machine gun fire.
The Afghan authorities have begun an investigation to find out whether any government officials might have been involved in the attack.
The break-out is a major security breach which will be of concern to both the Afghan government and security forces, our correspondent says.
Kandahar is one of the key battlegrounds in the Taleban's insurgency against President Hamid Karzai and Nato and US troops.
A Nato spokesman General Carlos Branco admitted the attack was a success for the Taleban, but said it was an isolated incident and did not mean the militants were gaining strength generally.
"I understand it was a very successful move for the Taleban, I'm not denying that, but we should not over react and exaggerate in the results... It's very soon to make an assessment and say that it was a strategic blow," he told the BBC.
Last month inmates at Kandahar jail ended a week-long hunger strike after a parliamentary delegation promised to address their demands.
Almost 400 prisoners said they had been denied access to fair trials and some also complained of torture.
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