A man (19) died last night after a two-car collision in Co Down.
Two people are being treated in hospital following the crash on the Ardglass Road, outside Downpatrick.
Police said the teenager was a front seat passenger in a silver Mercedes C220 when it was in a crash with another car shortly after 7 pm.
A PSNI spokeswoman appealed for anyone who was travelling on the Ardglass Road, three miles from Downpatrick, at the time to come forward.
Elsewhere, four people were injured early this morning when a car carrying eight people crashed in north Belfast.
The accident happened on Woodvale Road, close to Woodvale Park, shortly before 1 am. The driver of the car was later arrested.
In Co Down yesterday, a man (44) died after his bike collided with a car near Carryduff at around 2.30 pm. Police in Lisburn have appealed for anyone who witnessed the crash, which involved a Yamaha motorbike and a Citroen Saxo, to contact them.