Five people, including two young men and a two year-old boy, were killed on the roads over the weekend. This brought to 398 the number of road deaths in the State this year.
And three people died in fire-related incidents over the weekend.
The RUC has begun a murder inquiry into the death of a 44-year-old man in an arson attack in west Belfast on Saturday night.
Mr Stephen Gill (18) from Braddox and Mr Nigel Boyd (19) from Silverstream, both in Monaghan, died after the car in which they were travelling collided with a pillar near Emyvale, Co Monaghan, in the early hours of Saturday morning.
On Friday evening a pedestrian in his 60s died when he was struck by a vehicle in Quilty, Co Clare. Mr Joe O'Brien from Clonahinchy in Quilty was taken to Ennis General Hospital, where he later died.
In Sligo, a 63-year-old woman was killed near her home in Moneygold, Co Sligo, on Friday. She has been named by the Garda as Ms Grace McMorrow.
A two-year-old boy, Joshua Wilson, has died after the parked car he was sitting in was struck by another vehicle in Enniskillen, Co Fermanagh. His mother and three sisters were injured in the collision, which happened shortly before 8 p.m. on Saturday. The driver of the other car, a Volkswagen, was also hurt.
The boy died yesterday afternoon as a result of his injuries. His mother and 10-year-old sister are both in intensive care. The two other sisters, aged five and eight, and the driver are reported to be stable. Police in Enniskillen have appealed for witnesses to the accident to come forward.
On Saturday night Mr Michael McParland, aged 44, was killed in a suspected arson attack at Ross Cottages on the Falls Road in west Belfast. His body was discovered by the emergency services when they went to the house shortly after 10 p.m.
Following a post mortem late last night, an RUC spokesman said the man's death was being treated as murder. One arrest has been made.
The Northern Ireland Fire Service has expressed its concern over the alarming rise in the number of people dying in house fires in Northern Ireland. So far, 25 people have perished in house fires this year, compared with 16 in 1998.
A man in his early 20s died when a fire broke out in his mobile home in Ballymoney, Co Antrim, yesterday in the early hours. Two teams of firemen wearing breathing apparatus went into the mobile home and rescued the man but he later died in hospital. Another man in his 50s managed to escape from the blaze. The fire is believed to have been started accidentally.
Meanwhile, a woman in her 60s died when a fire broke out in her home on Plunkett Road in Finglas, Dublin on Saturday night.