Military spokesman Brigadier Prasad Samarasinghe said patrols had fought with clusters of rebels on the Tigers' side of forward defence lines that separate government from rebel territory in a northern swathe of the island called the Vanni.
"There have been several small incidents, but no major operation as such," he said. "They have been in the Vanni area, ahead of our forward defence lines."
The reported deaths come after the military claimed it killed 14 insurgents at the weekend.
The Tigers were not immediately available for comment on the incidents and there was no independent confirmation. Analysts say both sides inflate enemy losses and play down their own amid a propaganda war.
The foes on Tuesday each accused the other of shooting dead three civilians in the government-held eastern district of Batticaloa, as ordinary Sri Lankans continue to pay a heavy price for a conflict that has killed around 68,000 people since 1983.
The rebels warned on Monday their nascent air wing would launch more aerial attacks after a weekend raid on oil facilities near the capital.
Sunday's rebel air attack triggered air defences that plunged Colombo into darkness as tracers streaked through the night sky, forcing bars packed with fans watching their national side playing the cricket World Cup cricket final to shut early.
Sri Lanka's military is pushing on with a declared plan to wipe out the Tigers militarily, while the rebels have warned of a bloodbath as they fight on for an independent state for minority Tamils in the island's north and east.
In a bad omen for any hopes of halting the protracted conflict, the Tigers this week dismissed a new set of devolution proposals unveiled by President Mahinda Rajapaksa's ruling Sri Lanka Freedom Party.
Rajapaksa wants to devolve power at district rather than a higher level -- which analysts say is a non-starter and offers less devolution than at present -- insists on rebel disarmament and has flatly ruled out Tiger demands for a separate homeland for ethnic Tamils.
- Reuters - Thomson Reuters Foundation
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