Sri Lankan officials say a suicide bombing in the capital has killed at least 10 people and wounded more than 85 others.

Military spokesman Brigadier Udaya Nanayakkara says a suicide bomber crashed his motorbike into a bus carrying policemen in a busy commercial area in Colombo. At least eight of the people killed in the ensuing blast were police.

There has been no immediate claim of responsibility. But the spokesman blamed Tamil Tiger rebels for carrying out Friday's attack.

The blast took place near Sri Lanka's presidential office and military headquarters in a high-security zone.

President Mahinda Rajapaksa condemned the attack and appealed for calm. In a statement Friday, he accused the Tamil Tiger rebels of demonstrating a commitment to violence and terror, as well as contempt for democracy and human rights.

Tamil rebels have been fighting for an independent Tamil state in northern Sri Lanka since 1983.

Fighting has escalated since the government officially withdrew from a cease-fire deal earlier this year, charging that the rebels were repeatedly violating the truce.

Some information for this report was provided by AFP, AP and Reuters.