Bus bombing in Sri Lanka kills 21

At least 21 people were killed and 47 others wounded on Friday in the latest in a string of suspected Tamil Tiger attacks against civilians in the Sri Lankan capital, officials said.
The attack saw a packed state-run bus travelling just south of Colombo hit by a powerful fragmentation mine placed on the roadside and peppered with red-hot shrapnel.
"Twenty-one people have been killed, eight of them are women," police spokesman Ranjith Gunasekera told AFP.
Military spokesman Brigadier Udaya Nanayakkara blamed the Liberation Tigers of Tamil Eelam (LTTE). He said it was a "cowardly attack" by a "ruthless organisation."
Survivors said the bus was knocked over by the force of the explosion.
"I was standing in the middle of the bus when there was a loud noise and the whole bus toppled to the side," said 21-year-old office worker Shanika Priyadharshani while being bandaged up in hospital.
"I blacked out for a while. There was black smoke, people were dead around me. I shouted for help and someone pulled me out," she told AFP.
The defence ministry immediately sealed off the area, although no arrests have been reported. Police did, however, discover and diffuse another Claymore-type mine near the scene of the blast.
The attack was the third targeting commuters in and around Colombo in less than two weeks.
On Wednesday, 18 people were hurt when suspected Tiger rebels set off a bomb alongside a packed commuter train.
And on May 26, another attack on a commuter train - also blamed on the LTTE - killed nine people and wounded 84 others.
Each of the attacks came after the LTTE complained that government commandos, who operate in small groups known as "deep penetration units", have killed civilians in roadside bombings inside Sri Lanka's rebel-held north.
The LTTE said two civilians were killed late Thursday by a roadside mine in the north by an army unit, and that six civilians died in a similar attack on Monday night.
Last month, the rebels accused government commandos of killing 19 people in mine attacks.
Sri Lanka's military refuses to comment on its covert operations in the north.
Hostilities have escalated sharply since the start of the year when the government pulled out of a truce with the Tamil Tigers, who are fighting to carve out a separate Tamil state within the Sinhalese-majority island.
Since then, both sides have traded allegations that each others' forces are deliberately targeting civilians.
Casualty figures in the north are impossible to verify as journalists are barred from visiting front line areas or crossing into rebel-held territory.
The Sri Lankan government says that it now has the upper hand in the long-running conflict, with the defence ministry reporting that 4,081 Tamil Tigers have been killed so far this year.