A man has been arrested after three police officers escaped injury when their patrol was targeted in an explosive attack.
A device detonated in the Townsend Street area of Strabane, Co Tyrone, on Tuesday night.
The PSNI detained a suspect aged 20 in Newtownstewart on Friday morning. He has been taken to Musgrave police station in Belfast for questioning.
While detectives have said it was too early to attribute blame, suspicion will again focus on dissident republicans opposed to the peace process.
Detective chief inspector John Caldwell, who is leading the investigation, said: "We appreciate the understanding and patience of local residents as we continue to carry out our enquiries and would appeal for anyone with information about suspicious activity in the area to contact us."