A land mine struck a passenger bus crowded with civilians in northern Sri Lanka, killing at least 15 people and wounding 23 others Wednesday night, the military said.

The bus had been heading north from the agricultural town of Kabithigollewa near rebel-controlled areas when it was hit by the blast, said military spokesman Brig. Udaya Nanayakkara.

Evening buses in that area are generally crowded with farmers returning from the market in the town.

Initial reports said 15 people were killed and 23 injured, the military said in a statement.

The mine attack came exactly a week after two bomb attacks, blamed on the Tamil Tiger rebels in the area of the capital, Colombo, killed 20 people.

The earlier attacks occurred as the military renewed an offensive against the rebels in their home base in northern Sri Lanka.

A similar bus attack in the same area last year killed 64 people and provoked widespread military retaliation against the rebels.