Kean Wong:
At least seven people are killed and more than 60 wounded when a bomb exploded on a train during rush hour in the Sri Lankan capital.
Sri Lanka's military blamed Tamil Tiger rebels for planting the bomb on the train. The rebels have not commented on the bombing, but usually deny involvement in such attacks.

The latest blast came as the Sri Lankan military presses an offensive to retake the Tigers' northern stronghold. Just this weekend the military defused two powerful bombs on two buses over the weekend and has stepped up security in public areas.

Analysts say the military has the upper hand in the latest phase of the long-running war given superior air power, strength of numbers and swathes of terrain captured in the island's east. But they still see no clear winner on the horizon.