A military base adjoining Sri Lanka's only international airport has come under attack from suspected Tamil Tiger rebels, government officials say.
A military base adjoining Sri Lanka's only international airport has come under attack from suspected Tamil Tiger rebels, government officials say.
Witnesses reported hearing a series of loud explosions followed by gunfire.
Sri Lanka's air force says a light aircraft dropped two bombs on the base.
Passengers already on aircraft were disembarked and led to a shelter, while others trying to reach the airport were turned away and approach roads closed.
Passengers on aircraft at the airport next door were disembarked and led to shelter, while others trying to reach the airport were turned away.
The airport was attacked in 2001 by Tiger rebels who killed 18 people and destroyed civilian and military jets.
The base and airport were attacked in 2001 by Tiger rebels who killed 18 people and destroyed aircraft.
A statement from the Tamil Tiger rebel group, carried by TamilNet, has claimed responsibility for the attack and said that two aircraft were involved.
There is no word yet on casualties at the base, which is 30km (20 miles) from Colombo.
Panic
The BBC's Roland Buerk in Colombo says that people living near the airport were woken at about 0045 on Monday (1915 GMT Sunday) by a series of loud explosions, followed by gunfire.
The BBC's Roland Buerk in Colombo says that people living near the airport were woken at about 0045 on Monday (1915 GMT Sunday) by a series of loud explosions, followed by gunfire.
A police officer, speaking to the Reuters news agency, said that there had been a large explosion in a military area near the runway, where attack planes and helicopter gunships belonging to the air force were parked.
Vinodhan Joseph, who is in the area, told the BBC News website that he heard just under 10 minutes of explosions coming from the direction of the Katunayake base.
Air assault claims
The 2001 attack resulted in the loss of half the civilian fleet
There are reports that the assault may have involved an aerial attack by suspected Tamil Tiger rebels.
Neil Butler, a British passenger at the airport, told the BBC News website that he was inside the civilian terminal building when the attack happened.
Neil Butler, a passenger at the airport, told the BBC News website that he was inside the passenger terminal building and could hear the sound of machine guns and mortars.
"I heard a large thud and we all went to the window. There was a long silence and then several more explosions followed by machine gun fire," he said.
The 2001 attack resulted in the loss of half the civilian fleetThere is no word yet on casualties at the facility which is 30km (20 miles) from Colombo.
"The staff ran for the exit followed by the passengers. When I arrived downstairs in the check in area a large crowd was running in a panic from the entrance where there had been more machine gun fire."
Colombo airport is the country's only international passenger airport and it adjoins a military base, which houses some of the aircraft used in recent air strikes against Tiger rebel bases in the north of the country.
The air force base, which adjoins the country's only international passenger airport, houses some of the aircraft used in recent air strikes against Tiger rebel bases in the north of the country.
Sri Lanka has been sliding back into civil war for months, our correspondent says, and although a ceasefire does exist it is only on paper and both sides have been ignoring it for months.
Sri Lanka has been sliding back into civil war for months, our correspondent says, and although a ceasefire does exist it is only on paper and both sides have been ignoring it for months.
Our correspondent says that as the fighting in the north has worsened many people have been expecting the Tiger rebels to strike back in dramatic fashion in the south of the country, and it now appears that such an attack may be under way.
Our correspondent says that as the fighting in the north has worsened many people have been expecting the Tiger rebels to strike back in dramatic fashion in the south of the country, and it now appears that such an attack may be under way.
Tourism threatened
Tourism threatened
The island is heavily reliant on the money which tourism brings in, so an assault on the airport could be very bad news for Sri Lanka's economy.
The island is heavily reliant on the money which tourism brings in, so an assault on the airport could be very bad news for Sri Lanka's economy.
In the 2001 attack on Colombo airport, which involved suicide bombers, half of the country's national airline fleet was destroyed.
In the 2001 attack on Colombo airport, which involved suicide bombers, half of the country's national airline fleet was destroyed.
Sri Lanka's Tamil Tiger rebels have been fighting the armed forces of the predominantly Sinhalese government for much of the past 20 years.
Sri Lanka's Tamil Tiger rebels have been fighting the armed forces of the predominantly Sinhalese government for much of the past 20 years.
They want to establish an independent homeland in the north and east of the country.
They want to establish an independent homeland in the north and east of the country.
About 64,000 people have been killed and one million displaced by the fighting.
About 64,000 people have been killed and one million displaced by the fighting.
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