A five-year-old girl tonight became the third fatal casualty of the tragedy which saw a canoe capsize in a Highland loch.

Five-year-old Gracie Mackay, from the Muir of Ord, who had been seriously ill, has died in hospital, Northern Constabulary said in a statement tonight.

Police earlier named the two young brothers who died in a canoe accident and their father who is still missing.

Ewen Beaton, five, and his two-year-old brother, Jamie, were on board the six-man Canadian canoe which capsized in Loch Gairloch, near Ullapool, yesterday afternoon.

The search for their father, Ewen Fraser Beaton, 32, has been stood down for the day.

The family issued a statement through Northern Constabulary. It said: "We are utterly devastated by what has happened and the loss of our beautiful little boys. We appreciate all that has and is being done by emergency services to find their adoring father, Ewen.

"It is too difficult to say anything more at this time and we would appreciate our family being left in peace to grieve our terrible loss."

The brothers died last night after being plucked from the water and airlifted to Raigmore Hospital in Inverness.

Six people from two families - two men and four children - were on board the boat when it capsized.

Gracie Mackay's 35-year-old father and eight-year-old sister managed to swim to the shore.

Gracie was initially airlifted to Broadford Hospital in Skye, but was transferred overnight by rescue helicopter to the Royal Hospital for Sick Children at Yorkhill in Glasgow, where her parents were said to be with her.

Stornoway Coastguard was alerted to the incident at around 4.15pm yesterday after Mr Mackay and his elder daughter made it to the shoreline.

Peter Godding, sector manager for Stornoway Coastguard, said: "It's amazing really, she swam quite a long way in the sea, which is no mean feat. It's pretty incredible that she did survive, with the adult as well.

"She would have given the police certain information which they didn't have.

"The girl that survived is very courageous and very resourceful to be able to complete a 500-metre swim to shore. I mean, that's no mean feat for an adult but she's achieved that and managed in combination with the other adult to raise the alarm. She's amazing."

He described the search for Mr Beaton, which was stood down earlier today, as "extensive".

"The current situation is we've got one missing person who is a male adult. He has been in the water a very long time, if he is in the water. We have extensively completed a set of criteria which terminates the search. We've basically ticked all the boxes that says we don't need to search anymore," Mr Godding said.

"Miracles do happen sometimes, so there's always that at the back of our minds.

"We've covered the same ground over and over at least three to four times. The vessels at sea have been likewise, there's been two lifeboats here today and there were two here yesterday, and the sea area has been extensively covered. The airspace has been flown over yesterday by our aircraft and there was aircraft presence earlier on.

"The 60 square miles have been extensively searched and we've come to the end of what we can do."

When asked about the type of canoe the group had been on, he said: "They are quite cheap vessels to purchase and unfortunately it's quite difficult to maintain the stability if you stand up in them."

Yesterday, a helicopter and lifeboats from Portree, Gairloch and Loch Ewe launched a search and were involved in the operation to remove the three children from the water.

Local boats assisted rescue services in the search for Mr Beaton, which continued into the night in the water near the caravan park at Gairloch.

Today, police, Stornoway Coastguard, lifeboats from Lochinver and Portree and members of the Red Cross were involved in the search operation, which resumed at first light.

Gairloch and Lochinver Coastguard rescue teams have been searching the shoreline and outlying islands, helped by other local vessels.

The Maritime and Coastguard Agency said the search has become a recovery mission.

Rain and winds were forecast for much of the day in the area and choppy seas were understood to have made conditions more difficult for the teams.

Carol Collins, Stornoway Coastguard watch manager, said: "The weather is less favourable for searching today than yesterday but units have been out searching since first light.

"Sadly at this stage the search and rescue phase has now moved to a recovery mission."

Five-year-old Ewen Beaton was a primary one pupil at Teanassie Primary School, near Beauly, which is about 10 miles west of Inverness.

Highland Council said his brother was due to start nursery at the 61-pupil school at the end of the year.

Council leader Drew Hendry said: "This is a terrible tragedy that impacts on a close-knit community.

"On behalf of the council, I want to extend our deepest sympathies to the family. Our thoughts are with them at this very sad time."

Alison Donald, acting headteacher at the school, said: "As we are a small community, the school, parents and the wider community will feel this loss deeply."

James Martin, chairman of the school's parent council, said: "The school community is devastated by this tragic news.

"The Beatons are a well-known and highly respected family and the impact of their loss will be felt throughout the community."