The Maoists attacked a district jail in Kailali, near Kathmandu, on Wednesday night killing five security personnel and freeing 166 inmates including rebels, a state-run Nepal Television said.
This is the first major attack by Maoists after Nepal's King Gyanendra last Tuesday dismissed the Sher Bahadur Deuba government and assumed power.
Armed with crude bombs, the rebels broke open the prison gates after a 90-minute firefight with the security personnel, the TV report said. Four security men were injured in the attack.
The Kailali district administration office said the Maoists had also suffered heavy casualties but only one body was found.
A large number of security forces have been mobilised to search for the rebels.
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