A relative of murdered Limerick crime boss Kieran Keane was one of two men questioned by gardaí last night in connection with the discovery of a pipe bomb.
The man, who is in his 20s, was arrested at lunchtime on Sunday after he and another man in his 30s were noticed acting suspiciously near a shop in the Moyross area.
The two men are well-known members of a criminal gang based in the St Mary's Park area of the city.
During follow-up searches after their arrests, uniformed gardaí found a pipe bomb and some balaclavas in the rear garden of a house in Pineview Gardens, Moyross.
One of the theories being explored by gardaí is that the pipe bomb was intended for use in an attack against a rival gang member who is based in Moyross.
Both men were still being questioned last night under Section 30 of the Offences Against the State Act, which means they can be held for up to three days.
A spokesman for the Army bomb squad confirmed the device was a "viable pipe bomb" which could have had serious consequences if used.
Last March members of the bomb squad carried out a controlled explosion on a similar device which was also discovered in the garden of a house in Pineview Gardens.
Meanwhile, it has emerged that a teenager injured in a shooting in Moyross at the weekend is a relative of Aidan Kelly (19), from College Avenue, Moyross, who was shot dead in Blackwater, Co Clare, in May of last year.
The 18-year was in the passenger seat of a car at the entrance to the Pineview Gardens/Delmege Park area when at least three shots were fired at him at about 8.45pm on Friday.
Gardaí believe both this shooting and the discovery of the pipe bomb on Sunday are linked to a feud. However, it is not believed the pipe bomb was intended for use in a retaliatory attack for Friday night's shooting.