COLOMBO (AFP) -- Tamil Tiger rebels Monday shelled Sri Lanka's main military base in the island's north, defense officials said.

There were no immediate reports of casualties.
More than a dozen shells hit the Palaly military complex in the Jaffna peninsula on the northern edge of the Indian Ocean Island, officials said, adding that security forces were carrying out retaliatory strikes.
""About 15 shells had been fired,"" a defense official here said. ""Counter attacks are taking place.""
The guerrillas hold the southern part of the peninsula and there have been regular skirmishes along the frontlines.
The Colombo government pulled out of a Norwegian-brokered truce with the rebels this month, underscoring its recent statements that it has the upper hand in the drawn-out conflict.
Tens of thousands of people have died since the rebels launched their campaign to carve out an independent homeland for minority Tamils in the majority Sinhalese nation in 1972.