(CNN) -- Militants attacked a main prison in Afghanistan's Kandahar province Friday night, blowing its entrance open and allowing a large number of inmates to escape, provincial authorities said.
The militants used suicide truck bombs loaded with about two tons of explosives to blast holes in the mud brick walls of the Soviet-era prison, a Taliban spokesman said.
A gun and rocket battle between the militants and prison guards lasted several hours and ended with dozens of militants rushing inside on motorcycles to free all prisoners inside -- including about 400 Taliban fighters, the Taliban spokesman said.
The prison, located on the western outskirts of Kandahar city, held a number of arrested Taliban figures. Several had recently embarked on a hunger strike.
A Justice Ministry official said about 1,000 inmates were inside the prison. Nine guards, seven prisoners and one civilian were killed in the attack, according to Ahmad Wal Karzai, the brother of Afghan President Hamid Karzai.
Checkpoints were set up around the prison in an attempt to catch the escapees, one police officer said. Authorities had also requested assistance, such as a helicopter, from nearby Canadian forces.
The government announced a state of emergency for the province and urged residents to stay home.
Earlier Friday, about 100 Taliban militants launched an attack against coalition troops, an assault a U.S. military official called the "largest" this year so far by the Taliban.
The incident occurred in southern Afghanistan's Uruzgan province. The coalition said militants attacked Afghan and coalition forces with small arms and rocket-propelled grenades, then fled to a village.
"Coalition aircraft engaged the positively identified enemy position with a precision airstrike," the U.S.-led coalition said in a statement.
The fighting began Thursday when Taliban militants ambushed a U.S.-Afghan patrol.
"While investigating an area used by militants... the combined patrol was ambushed by militants with small arms and indirect fire. The combined patrol returned small-arms fire, and the militants moved into a fortified position near an orchard.
"The combined patrol observed numerous noncombatants fleeing the area. Once the area was assessed to be clear of noncombatants, the combined patrol confirmed positive identification of the militants' position and requested support from coalition aircraft. Coalition forces directed one precision airstrike, followed by air-to-ground gunfire on the positively identified enemy positions," the coalition said.
Troops stayed in the area overnight "to provide security for the local populace," and the 100 militants then launched its attack.
Also on Thursday, two British soldiers were killed and a third was wounded in neighboring Helmand province when they were assaulted by insurgents, the British Defense Ministry said.
A Romanian soldier was killed on Friday during violence in the Qalat district of the southern province of Zabul, the country's Defense Ministry said. Three other Romanian soldiers were injured. The soldiers are part of NATO's International Security Assistance Force.
CNN's Barbara Starr and Journalist Farhad Peikar contributed to this report.