A brother and sister were fighting for their lives in hospital last night after a serious car crash in Creggan, near Randalstown, Co Antrim.
The two children were hit by a white Audi A3 at around 4.40pm yesterday after getting off a school bus.
They had been crossing the Staffordstown Road at the junction with the Greenan Road.
The ages of the two young people are not yet known, but it's understood they are pupils at St Patrick's College in Maghera.
A spokesman for the Northern Ireland Ambulance Service said two emergency vehicles were dispatched after being alerted around 4.50pm.
The siblings were taken to Antrim Area Hospital first with plans to transfer them to the Royal Victoria Hospital in Belfast. They were in a critical condition last night.
Sinn Fein MLA Declan Kearney said it is a "devastating" accident.
"They were alighting from the school bus and in the process of walking home," he said.
"It is devastating for their family, they come from an extremely well-respected, well-liked family within the greater Creggan area," he added. "My thoughts, and that of the wider community of Creggan, and neighbouring areas, are with their parents, and other family members at this time."
Last night the car involved in the crash remained at the scene, with the Staffordstown Road closed in both directions.
DUP councillor Trevor Beattie, who lives in Randalstown, said it was "a sad situation." "It's a very busy road - unfortunately one with a speeding issue, although I'm not saying that was the case this time," he said.
"These small country roads in the Randalstown area can be dangerous and extra care has to be taken.
"Obviously our thoughts and prayers are with the families concerned as nobody wants to be faced with something like that. It's a tragic event and I hope they both make a full recovery."
SDLP councillor Roisin Lynch said: "My immediate thoughts and prayers are with the two children who remain in a critical condition following this terrible crash.
"My thoughts and the thoughts of the entire community will also be with their families at this incredibly difficult time.
"I would appeal to anyone who was travelling along the Staffordstown Road area this afternoon at around 4.40pm and who may have any information that might be useful to police to bring it forward as soon as possible.
"This incident has shocked local people and I have no doubt that they'll do everything they can to help. This is an horrific experience for any family to go through. I will be following up with local agencies to explore if there's anything that can be done to enhance safety in the area."
The PSNI has appealed for witnesses to contact officers at Antrim on 101 quoting reference number 740 17/01/17.