Colombo: Sri Lankan police today arrested a retired Deputy Inspector General who became the second senior police officer to be held for the killing of a leading newspaper's editor and a vocal critic of former president Mahinda Rajapaksa, officials said.

Lasantha Wickrematunga, the founder and editor of the Sunday Leader, was waylaid by some unidentified bike-borne assailants who gunned him down in the Colombo suburb of Ratmalana in January 2009.

The retired DIG Prasanna Nanayakkara was arrested for alleged tampering of evidence. He became the second senior policeman to be arrested in the case. On February 3, the former acting crimes Officer in Charge (OIC) of the Mount Lavinia Police was also arrested and remanded.

Nanayakkara was serving the Western Province (South) Police division when Wickrematunga was murdered in broad day light in 2009. The murder was blamed on the then administration of the former president Rajapaksa.

Wickrematunga was a fierce critic of the Rajapaksa government. His murder was in the forefront of cases of rights abuses blamed on the Rajapaska government. The current government has faced public resentment over the sluggish progress in taking the culprits under the former regime to book.

At this weekâ€™s local council election, Rajapaksaâ€™s new political party, Sri Lanka People's Party (SLPP) recorded a resounding victory. The government's defeat in the election has been attributed among other things to slow judicial process to investigate crimes under the former regime. (PTI)