Two men were being questioned by gardaí in Limerick last night in connection with last week's gangland murder of father-of-six, John Ryan.
The men - one in his 20s and one in his 40s - were arrested by gardaí in the Island Field area on the north side of Limerick city at about 8.30 a.m. yesterday.
They were being detained for questioning last night under section 30 of the Offences against the State Act at Henry Street and Mayorstone Garda stations.
Mr Ryan (47) was shot dead by one of two men who approached on a motorcycle as he worked on a neighbour's front garden patio in Canon Breen Park, Thomondgate, at teatime last Monday week.
Yesterday's Garda operation brings to four the number of people arrested in connection with his murder although no one has yet been charged.
Meanwhile, Supt Willie Keane - who is leading the Garda investigation into Mr Ryan's murder - has issued a fresh appeal for witnesses to the shooting to come forward.
"We are particularly anxious to speak to a couple who were seen pushing a child's buggy near Frasier's pub in Thomondgate at 6.25 p.m. last Monday week, as they may have valuable information.
"We would also like to hear from three young girls who were spotted walking just behind the couple on the night in question," Supt Keane said.
Gardaí confirmed last night that they were still awaiting the results of ballistic tests carried out on a handgun.
These should determine whether it was connected to this latest gangland killing.
The weapon was seized along with some €10,000 in cash and a quantity of amphetamines following a number of dawn raids in the Island Field area.
The 125 cc motorbike which gardaí believe was used by the killers was also recovered in the Island Field last week.