Sri Lanka's former army chief told parliament today that a bomb blast apparently targeting former president Mahinda Rajapaksa's brother 10 years ago was an "inside job" to win sympathy for the then-ruling family.

Sarath Fonseka, now a government legislator, said the December 2006 bomb attack blamed on separatist Tamil Tiger rebels had been stage-managed by the president's brother Gotabhaya Rajapaksa, the then defence secretary.

"No terrorist will set off a suicide bomb 25 meters away from the intended target," Fonseka told parliament during a debate on scaling down military security granted to the former strongman leader.

The government has said it is removing troops in Rajapaksa's bodyguard and replacing them with police commandos as part of a policy of relieving the military from civilian security duties.

Gotabhaya escaped the 2006 bombing in Colombo unhurt but it killed two members of his military convoy.

Soon after the attack, the government asked peacebroker Norway to halt all contacts with the Liberation Tigers of Tamil Eelam. Colombo withdrew from a truce and eventually crushed the rebels by May 2009.

The former army chief led the successful military campaign against the Tigers, but later fell out with the Rajapaksa family over who should take credit for the spectacular military success.

He launched a failed challenge to Rajapaksa in 2010 elections and was later jailed for two and a half years on corruption charges.

The former army general has since been exonerated of all charges and elevated to the rank of field marshal by Rajapaksa's successor, Maithripala Sirisena.

The general himself was seriously wounded in a suicide bombing in April 2006.

He recovered to lead the military in wiping out the rebel leadership in a no-holds-barred offensive that also sparked allegations of war crimes.

(PTI)