SRI LANKA ? Tamil Tiger rebels used at least one small propeller plane to bomb a Sri Lankan air force base Monday outside the capital – the separatists’ first airstrike in their quarter-century fight against the government. Three airmen were killed.

The attack had limited military significance, leaving aircraft on the ground unscathed. But it had great psychological impact, showing the rebels have a new weapon they can use to strike deep inside the southern heartland of the Sinhalese majority.

The airstrike “adds a new dimension to the two-decade separatist war,” said Iqbal Athas of Janes Defense Weekly. “So far the Tigers have fought only in the sea and land but the very fact that they have used their air capabilities, however limited they may be, has enhanced the threat factor which the security forces need to be mindful of.”

The government retaliated with air raids on rebel positions in northern Sri Lanka. No casualties were reported.