A major search operation for three people missing on a fishing boat from Conwy will resume on Friday morning, the coastguard has said.
The Nicola Faith vessel was expected back in the port at midnight on Wednesday.
But the fishing boat was reported missing to the HM Coastguard shortly after 10:00 GMT on Thursday.
A search involving seven RNLI lifeboats, a helicopter and fixed-wing plane was suspended at about 21:00 GMT.
Rescue teams from Rhyl, Bangor and Llandudno Coastguard Rescue Teams were sent to assist the search, along with seven RNLI lifeboats from Rhyl, Llandudno and Conwy.
As well as the coastguard search and rescue helicopter from Caernarfon, a fixed-wing coastguard aircraft also took part in the operation.
At about 20:00, the Beaumaris, Conwy and Llandudno inshore lifeboats returned to their stations having been stood down, with the all-weather boats from Rhyl, Llandudno and Hoylake remaining at sea a while longer.
The entire search was then suspended for the night, with "a further search planned for first light" on Friday, the coastguard said.
An RNLI spokesman told BBC Wales: "Absolutely every effort is being made to find the missing vessel and our thoughts are clearly with the family, who are clearly worried about their loved ones at this time."
Rhyl RNLI volunteer Paul Frost said the 10m (33ft) fishing vessel was last seen at 22:00 on Wednesday night, off Rhos-on-Sea.
He added the search operation was being heavily-resourced as it covered a huge area.
"It is literally hundreds of square miles, the area searched is something like 30 miles across by about 15 miles out as well. That's why so many resources have been utilised to try and search the area adequately," he said.
"It's very, very cold but the sea conditions aren't too bad. But the problems now are exacerbated by the oncome of night which makes searching more difficult."
North Wales Police was also involved and an alert was sent to other boats in the nearby area, a coastguard spokeswoman said.
As it grew dark, duty controller for HM Coastguard Rob Priestley said: "We are continuing to search a wide area to try and find this vessel with all the assets we have at our disposal. We're also asking other vessels in the area to keep a look out for anything that might also assist the search."
The boat was said to have left Conwy yesterday to go fishing and hadn't returned.
It was due to return at midnight last night, but the alarm was raised round about 10am this morning when the emergency services were contacted.
Holyhead coastguard have been coordinating the search during the course of the day.
They've had a quite considerable number of resources - we're talking about three coastguard team volunteers on the land, searching the coast, out at sea; seven lifeboats, which lifeboat crews say is a very unusual amount of lifeboats all at one time, all on the same job, all out searching a very wide area; and then up in the air above there's been a coastguard helicopter and a fixed-wing aircraft as well.
It's covering a very large area, as far east as Rhyl where, off the coast there, people have spotted search activity going on, and as far west as Beaumaris and Puffin Island, that area just off the coast of Anglesey was brought into the search area this afternoon.