The suspect was arrested in Lurgan last night and was being questioned by detectives from the PSNI’s serious crime branch.
A PSNI spokesman said the man was assisting police with enquiries at Antrim PSNI Station.
The crude device went off without warning at Levin Road. There were no reports of any injuries and only minor damage was caused.
Police had been in the area at the time investigating reports that an illegal republican parade was due to take place.
Dissident republicans – who have been behind a number of shootings and bombings in recent weeks – have been blamed for the attack.
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