Sri Lanka's Criminal Investigations Department (CID) made the announcement, stating the the blood samples of Sri Lankan navy personnel suspected of carrying out the execution had been dispatched for testing.
It follows the arrest of three members of the navy, including two officers, for the November 2006 murder.
Mr Raviraj, a human rights lawyer and MP with the Tamil National Alliance, was widely respected and was conferred the highest civilian honour of the LTTE, the Maamanithar award, in 2006. Thousands of Tamil-speaking people observed shutdowns across the North-East, and the up-country, in protest at his killing.
Then-President Mahinda Rajapaksa ordered an inquiry and two suspects, Nalaka Mathagaweera and Aruna Shantha Ediriweera, were arrested in 2007. Mr Rajapaksa requested assistance from Britain’s Scotland Yard, who sent a team to work with the Criminal Investigation Department, who looked at evidence. Nothing came of the inquiry.
See our earlier post:
Arrests (again) over killing of TNA MP Raviraj (31 Mar 2015)
Also see:
Tamil Parliamentarian Raviraj assassinated in Colombo - TamilNet (10 November 2006)
People of Jaffna pay last respects to Raviraj - TamilNet (14 Nov 2006)
Thousands pay homage to Raviraj in Colombo - TamilNet (14 Nov 2006)
Government blamed for TNA MP's killing (15 Nov 2006)
Anger and frustration (15 Nov 2006)
NorthEast mourns for Raviraj - TamilNet (15 Nov 2006)
Kilinochchi remembers Raviraj - TamilNet (16 Nov 2006)
British forensic officers study Raviraj exhibits - TamilNet (13 Jan 2007)
Raviraj murder inquiry fixed for January 2 - TamilNet (22 Dec 2007)
Court extends remand for suspects in Raviraj, Maheswaran killings - TamilNet (17 Apr 2008)
New govt to investigate assassination of 2 TNA MPs during Rajapaksa reign (22 January 2015)