A 35-year-old woman died in south Armagh when her car was in collision with a lorry on the Concession Road outside Crossmaglen.
The driver of the Volvo lorry suffered minor injuries in the collision with the Renault Megane in which the woman was travelling.
The death increased the toll on the roads to 129 so far this year. Earlier police named two men who died after a road accident in Co Down on Monday night.
They were 25-year-old Paul Shaw of Court Street, Newtownards, and Philip Harkness, 19, from the Belfast Road, Comber.
The two died in an accident involving two cars on the Kempe Stones Road. The men were in separate cars, a woman passenger travelling with Mr Shaw and the woman driving the car in which Mr Harkness was the passenger, were injured.
Neither of them were understood to have suffered life-threatening injuries. On Sunday a 22-year-old man and a 15-year-old girl were killed in a crash on Belfast's Falls Road.
Three other people were critically injured in the collision between a car and a taxi and five more suffered lesser injuries.