Two bombs ripped through separate cars of a commuter train Wednesday, leaving bodies, briefcases and other debris scattered in the wreckage. At least 63 people were killed and more than 350 wounded in the attack blamed on Tamil separatist rebels.

It was the worst terrorist attack on the Sri Lankan capital since a Tamil Tiger suicide bomber devastated Colombo’s commercial district in January, killing 88 people.

The bombings occurred as 2,000 Sri Lankan army reinforcements reached a major military base in the northeast, where the government had just suffered one of its worst defeats in 13 years of civil war.

Of the 1,200 soldiers who had been manning the base when rebels seized it last week, the reinforcements found only 11 survivors hiding in a well, military officials said.

Attacks on both military and civilian targets in one week showed the Tigers are not backing down, despite several months of government victories that had given some Sri Lankans hope the war was ending.

The two bombs exploded simultaneously in separate cars of the train, which was pulling out of a station in Dehiwala, a middle-class suburb just south of Colombo on the Indian Ocean coast. Police said the bombs were concealed in parcels.

Rescuers making their way through the blasted-out cars found bodies lying among shoes, briefcases, handbags and other debris. Hundreds of people were taken to hospitals.