Sri Lankan former army chief Sarath Fonseka could use his new position as an opposition law-maker to revive calls for an international war crimes investigation, the government said Thursday.
Troops wiped out Tamil Tiger rebels, who had fought for a Tamil homeland for decades, one year ago in a ferocious military offensive that caused widespread humanitarian concern.
The United Nations reported that at least 7,000 civilians perished during the last four months of fighting, and it also accused the Tiger guerrillas of using civilians as human shields.
"Those bent on destabilising the country would now exploit Fonseka's parliamentary privileges to fast track their sinister campaign (for a war crimes probe)," Defence Secretary Gotabhaya Rajapakse told the Island newspaper.
Fonseka, the architect of the military offensive, fell out badly with President Mahinda Rajapakse, Gotobhaya's brother, after their victory over the Tigers and unsuccessfully tried to unseat the president in January elections.
Fonseka is now being court martialled, but won a seat in parliament last month. He has accused Gotabhaya of ordering the execution of Tamil Tiger rebels as they surrendered.
Sri Lanka has strongly resisted calls for an international investigation into alleged war crimes, saying no civilians were harmed by government forces in its battle against the Liberation Tigers of Tamil Eelam (LTTE).
Sri Lanka insists it carried out a "humanitarian operation" to free Tamil civilians from rebel control, but the UN and Western nations, including the United States and EU member states, have called for an investigation.