A 21-year-old man has been killed in a crash between a coach and a car in Co Antrim while four people were taken to hospital following a collision involving four motorbikes and a car in Co Down.
The man was killed in a crash outside Ballymena.
Inspector David McCausland said: "The incident occurred at Moorfields Road at about 1pm and involved a car and a coach."
Ballymena TUV councillor Stewart McDonald said: "I'm saddened to learn of the death of this young man and my thoughts and prayers are with his family at this time as they come to terms with his death.
"I hope all those on the coach are OK, as they will also have endured a traumatic event.
"I'm waiting to hear from the PSNI as to the circumstances surrounding the collision and if there are any issues with the road itself I will raise it with Transport NI."
Meanwhile, four people were injured in a road traffic collision near Mayobridge outside Newry yesterday.
The incident involved four motorcycles and a car and happened shortly before 2pm.
The crash appeared to have happened at a junction with a side road and all the bikes ended up lying fairly close together.
One of the motorcyclists was airlifted by police helicopter to the Royal Victoria Hospital in Belfast.
Two were taken to Craigavon Area Hospital and the fourth person was brought to Daisy Hill Hospital in Newry.
All of them were understood to be in a stable condition last night.
An eyewitness to the aftermath of the collision said: "There were four bikes and a car damaged.
"It was a very dramatic scene with a lot of damage to the bikes.
"There are pieces lying all around the place and a bike is wrapped around a B&B sign.
"It is the worst scene I have ever seen with motorbikes."
Neighbours also spoke of their shock at the severity of the accident.
One man said: "The road was closed off.
"We all hope everybody recovers."
SDLP councillor Gillian Fitzpatrick said: "I was shocked to hear about the accident involving a car and motorcycles at the Aughnagon Road. One of those involved is a neighbour of mine and the incident has left the whole community shaken.
"My thoughts are with all those injured in this awful accident, especially the motorcyclist who has been airlifted to the Royal Victoria Hospital in Belfast.
"I hope and pray that everyone involved makes a complete recovery.
"I have no doubt that the Mayobridge community will provide whatever help and support they can to all those involved during this difficult time."
Police are appealing for anyone with information about either of the collisions to get in touch with them.
The man's death in Ballymena brings the number of people killed on the roads this year to 43.
At the same time last year 49 people had lost their lives on Northern Ireland's roads.