4 men have been arrested in connection with the murder of Aidan Byrne in Dublin 7 months ago.
The 32-year-old father of one was shot dead while sitting in a car just off the North Circular Road in February.
The men were all detained in Dublin this morning.
They are aged in their 20s and 30 and are currently detained under Section 50 of the Criminal Justice Act.
They are being questioned at 4 Garda stations across the capital.
