Road deaths in the North are occurring at almost the same rate as in the South so far this year, despite the fact that the Republic's population is more than twice as large.
The deaths of two teenage girls in Co Antrim early yesterday brought January's road fatalities in Northern Ireland to 18, compared with 19 in the Republic.
The girls died when the Ford transit van in which they were front-seat passengers crashed into a gate and then a tree at Carlane Road, Toomebridge, at 12.30 a.m. yesterday.
No other vehicle was involved in the crash.
Police named the victims last night as Ms Christina Maguire (15), of Cargin Road, Toomebridge, and Ms Catherine Graham (14), of Brecart Rd, also in Toomebridge.
Two teenage males and a teenage female were injured in the collision.
The youths were reported to be in a stable condition in hospital, while the girl suffered whiplash and shock.
Eleven of the 18 road victims to date were 18 years or under.
The road deaths toll is three times that of the same period in January last year, when six people died on the roads.
Insp Gordon Scott of the Police Service of Northern Ireland described the accident as another "unbelievable" tragedy in the "culture of death on our roads".
He said motorists must start heeding the dangers of driving.
Road deaths in the Republic are well down on last year, when 36 died during January.
However, gardaí in Charleville, Co Cork, are appealing for witnesses following the latest fatality.
Mr Martin Hickey (21), from Milford, Co Cork, died shortly after 8.30 p.m. on Saturday night when the car in which he was a front-seat passenger collided with a tractor at Smith's Road, Kippane.
The driver of the car was taken to hospital for observation but later discharged.
Elsewhere, gardaí at Navan are investigating a fatal hit-and-run accident at Donaghmore, on the Navan to Slane Road, on Friday night.
Two pedestrians were walking towards Navan at about 10.10 p.m., when they were struck by a car which failed to stop.
Both men were removed to Our Lady's Hospital, Navan and one later died from his injuries.
The victim was named last night as Mr Desmond Kellett (34), from Closker Park, Navan.
The injuries to the second pedestrian, an 18-year-old, are not life-threatening.
Back in the North, two men were arrested and six police officers injured when a VW Vento crashed into two stationary cars, one of them a police Land Rover, in north Belfast around 3.40 a.m. yesterday, according to the PSNI.
Four of the officers were injured in the initial collision at North Queen Street.
The driver of the Vento was arrested.
Two other officers were assaulted by a passer-by who intervened in the incident, said police.
This man was also arrested.