The man aged in his mid-50s was arrested this afternoon
Gardaí have arrested a fourth man in connection with the murder of David Byrne at the Regency Hotel in Dublin.
Mr Byrne was gunned down at the venue in February, as part of the violent Kinahan-Hutch gangland feud.
The man aged in his mid-50s was arrested this afternoon.
He is being detained at Raheny garda station under Section 50 of the Criminal Justice Act.
Last night, a father and son were arrested in relation to the investigation - while on Friday night a man was also taken into custody.
It brings to four the number of people in custody at several garda Stations across the city.