The man who died following a suspected hit-and-run in Castlebar has been named locally as Denis Provirnevs.
The 45-year-old Latvian national was struck by a vehicle in the Humbert Way area of the town shortly before midnight on Wednesday.
He later died from his injuries at Mayo University Hospital.
Gardaí have arrested a man in his late 30s, in relation to the fatal collision.
The man is currently detained under Section 4 of the Criminal Justice Act in Castlebar Garda Station.
Investigations are ongoing.
