OLOMBO -- At least nine people were killed when a suicide bomber detonated explosives strapped to her body at a military checkpoint here in the capital today, the police and witnesses said.
No group claimed responsibility for the blast, which left charred limbs littering the area, and the Government did not blame anyone.
But security forces have been on alert for attacks by separatist Tamil Tiger rebels during festivities marking the 50th independence anniversary of the nation this week.
The explosion happened only hours after Prince Charles left at the end of a four-day visit to mark the anniversary.
The Liberation Tigers of Tamil Eelam are fighting for a separate homeland for minority Tamils in Sri Lanka's north and east. The Government says that 50,000 people have been killed in the fighting that erupted in 1983. The Tigers say the toll is higher.
A senior police official at the site of the explosion said the dead included three civilians, one of whom was the woman who detonated the explosives she was carrying after being asked to step out of a van at the checkpoint.
Two soldiers and three members of the air force also died.
The van was not heavily damaged and police officials said they had recovered an identity card that they believe belonged to the bomber.
Scores of soldiers and police officers sealed off the area, where large crowds had gathered.
"This has been expected for a long time, but they have been obviously prevented from carrying out a big attack," Inspector General of Police Wickremasinghe Rajaguru said at the scene. Health officials said five people were admitted to hospitals. They said one, believed to be the driver of the van, later died, bringing the toll to nine.
The explosion occurred near the air force headquarters and the Trans Asia hotel shortly before offices closed for the day.
The explosion was heard across the city center, sending office workers rushing to their windows.
Tight security in Colombo brought life to a halt while Prince Charles was in town as thousands of Government troops and police officers set up hundreds of checkpoints and sealed off parts of the city.
The Government blamed the rebels for a blast in the central city of Kandy last month that killed 16 people and forced the Government to shift the independence celebrations to Colombo.
It also blamed the rebels for a truck bomb that went off last October in the Colombo business center. That blast killed 18 people.