One more person arrested in connection with the attack on an Army convoy some two months ago on the outskirts of the city, was detained under the National Security Act (NSA) on Sunday.
An order to this effect was served on Veluchamy, an MDMK worker in Arasur, lodged in Central Prison in Coimbatore on Sunday evening, police said.
Three of the 42 persons arrested have already been detained under NSA. Ten were released on bail a couple of days ago.
Police have registered cases against 200 persons,belonging to various pro-LTTE parties and organisations, for their alleged involvement in the attack on an Army Convoy on May 2.
The military convoy, comprising 80 trucks with army personnel and training materials, was returning to Madukarai regiment near here from Hyderabad when it was attacked by a group of nearly 200 people, belonging to different pro-LTTE outfits at Nilambur Bypass that day.
The outfits suspected that the convoy had weapons and arms to be supplied to Sri Lanka to crush innocent Tamils.