Foul play is now suspected in the death of a policeman on duty at the Peliyagoda interchange of the expressway in the early hours of 06 December.
It was previously believed Sub Inspector Rohitha Ruwan Kumara had shot himself.
Reports now say he was killed to prevent him from taking legal action against the paramour of a powerful politician, who was caught violating traffic rules on the expressway that same day.
CCTV footage of that incident has now been deleted.
Contrary to a claim that he shot himself with his service pistol, physical evidence shows a big gap from the range of fire and his neck, from which the bullet entered his body.
The website 'Lanka Truth' first reported about the suspicious nature of the policeman's death.
