A 39-year-old man arrested by gardai investigating the gun murder of Benny Whitehouse last year is being questioned about disposing of a getaway car involved in the killing.
The suspect, from Co Louth, is a key member of the gang who murdered Whitehouse but is not believed to have been the hitman.
Whitehouse (35) was shot dead in front of his partner outside a school in Balbriggan last September.
The arrested criminal, who is a well-known drug dealer, was picked up by armed officers in Ardee, Co Louth, yesterday morning and was still being questioned at Balbriggan Garda Station last night.
Whitehouse was shot dead at Clonard Street, Balbriggan, at 9am last September 25, and a major investigation into the feud-related killing has been continuing for four months.
Gardai have seized the stolen car they believe was involved in the murder. It has also emerged that the vehicle's registration plate has been cloned at least twice.
It is believed Whitehouse was murdered by a gang whose stronghold is in north Dublin and south Louth.
An English criminal who is now serving a jail sentence is suspected of having acted as a getaway driver for the shooting which had been planned for weeks.
Whitehouse had been involved in a bitter feud with this crew whose leader is facing serious charges before the courts.
He has linked up with a major crime gang from Swords and has been trying to exert control over the crime scene in north Co Dublin and south Co Louth for the past two years.
Last month, the Herald revealed that a bogus assassination incident in Clondalkin on the night of last January 3 was a botched attempt by a major gangster suspected of being involved in ordering the Whitehouse murder to get his bail conditions changed.
The feared criminal at the centre of the staged hit is a key player in the mob involved in Whitehouse's murder and enlisted associates for the farcical 'hit' in which no shots were fired.
He has since had his bail conditions changed.