Two adults and three children died and a four-month-old infant was rescued after their car plunged into the sea off a pier in Co Donegal last night.
The horrific incident happened in Buncrana around 7.15pm at a popular Wild Atlantic Way stop-off point for tourists wanting to watch the sun set over Lough Swilly.
The town had been packed with visitors on a bright and sunny Sunday at the start of the Easter holidays.
A four-month-old baby girl was thrown from the Northern Ireland-registered Audi Q7 jeep as it went off the pier.
Two local men managed to rescue the infant, who was rushed by ambulance to Letterkenny University Hospital.
However, the other five occupants of the 4x4 - believed to be visitors - tragically drowned.
The Coast Guard 118 Rescue helicopter, RNLI lifeboat crews from Lough Swilly and Greencastle, ambulance crews and gardaí all took part in the search and rescue operation.
But by 9pm it was clear that there were no other survivors.
The children who died included two boys, believed to be of national school age, and a girl.
According to locals, Buncrana is an extremely popular spot with people from Northern Ireland, especially Derry which is located only 26km away.
It is believed the group may have travelled from Derry to Buncrana as it's a popular spot on the shores of Lough Swilly.
Emergency services continued to scour the shoreline late into the night as the scale of the horrific tragedy became clear.
"Once again, Inishowen has been hit with a terrible, terrible tragedy," said local councillor Jack Murray, who was at the scene.
"We knew that something awful had happened when we saw all the emergency services and lifeboat volunteers at the pier but we weren't prepared for the full horror of it.
"Buncrana is in mourning again. It's like the Inishowen car crash all over again.
"We believe those who died were not from here and may have been visiting and enjoying a lovely sunny Sunday and then this dreadful incident happened.
"A family somewhere is about to get the most awful news. We'll pray the young child survives," he added.
"It was the most awful scene," said one local man.
"The emergency services worked tirelessly to try to rescue the family but there was little they could do other than to try to recover them from the water as quickly as possible."
Local people said there had been a number incidents in recent months of cars parking on the slipway getting into difficulty when their vehicles slid into the water. The slipway has been covered in a thick layer of algae.
Gardaí sealed off the scene and a full investigation into the tragedy will begin at dawn today.
However, it is believed the car may have accidentally slipped into the water.
A large crowd of around 200 people stood in silence at the pier last night as the search continued.
The bodies of the couple and the three children were taken to Letterkenny hospital, where post mortems are expected to be carried out today.
Eyewitnesses described the scene at the pier as "absolutely manic" as emergency services desperately tried to rescue the family.
"There were dozens of gardaí, fire units and water rescue teams. They managed to pull one child out in time, but it doesn't seem like they got to anybody else in time."
Those wishing to pay their respects will be able to sign a book of condolence in the coming days.
The book will be available to sign in the Guildhall, Derry.
Mayor of Derry, Elisha McCallion, said she will open the book in response to the tragic incident that claimed the lives of five people.