Hit-and-run driver arrested
The man, aged in his 20s, is being questioned under Section 4 of the Criminal Justice Act and can be held for two days.
The collision took place on the Kinnegad to Edenderry Road at Carrick, about five kilometres from Carbury, Co Kildare, just before 9pm on Tuesday.
A male cyclist, aged 61, received fatal injuries. nLeixlip Garda Station on 01-6667800, the Garda Confidential Telephone Line 1800 666 111 or any Garda station.