Snow fell heavily in Lerwick

An estimated 70,000 children missed classes as severe weather led to the closure of more than 300 schools - with many due to be shut again on Thursday.

Drifting snow was causing difficulties on many roads and police appealed to drivers in affected areas to avoid travelling unless absolutely necessary.

The worst hit areas were the Northern Isles, Highlands and the north east.

Grampian Police warned that conditions were "very hazardous" on most roads, due to a combination of drifting snow and broken-down vehicles.

"Our advice for motorists is not to travel in the Aberdeenshire area unless absolutely necessary," said a spokesperson.

In pictures: Scotland's cold snap

Moray Council admitted that it was losing the battle to keep its roads open.

The local authority said it would stop road clearing efforts at about 2100 GMT and warned that the majority of routes in the area would become impassable.

Most schools in Aberdeen city were closed, more than 30 schools in Moray were shut and about half of the schools in the Highlands were affected.

There were also school closures in Tayside, Dumfries and Galloway and Borders.

All schools in Aberdeenshire, Moray, Orkney and Shetland will be closed on Thursday.

Flights in and out of Aberdeen, Orkney, Shetland and Inverness airports were affected on Wednesday.

Snow gates

British Airways later announced the cancellation of flights from London to and from Glasgow, Edinburgh, Aberdeen and Inverness.

A number of Thursday morning's flights between London and Glasgow, Edinburgh and Aberdeen were also cancelled.

Roads officials said persistent heavy snowfalls had caused difficult driving conditions on parts of the A90, the A96 and the A9.

Snow gates on the A93 were in use both sides of the Glenshee ski centre.

Snowfalls in the Borders were also causing problems on a number of routes.

Northlink said it had cancelled its sailings from Aberdeen and Shetland on Wednesday evening.

Snow fell in Glasgow on Wednesday morning

The winter weather caused power cuts in the Western and Northern Isles.

About 70 homes across Shetland faced a night without electricity, including the 18 houses on the island of Papa Stour - which had been without power all day.

Two climbers, one male and one female, were rescued by members of RAF Lossiemouth after being reported overdue from a climb on Black Spout Gulley on Lochnagar, near Ballater, Aberdeenshire.

The helicopter crew picked up the pair while weather conditions were clear, but on its way back to Ballater heavy snow showers hampered the journey.

The Scottish SPCA has urged the public to make the necessary provisions for pets and livestock during the wintry conditions.

Damaged properties

Farmers with livestock should ensure that their animals have adequate shelter and food during the cold weather, the charity said.

Motorists have been advised to carry warm clothes, food, water, boots, a torch and a spade when driving in snow.

The Automobile Association said it was preparing for a breakdown rate of up to 20,000 a day - compared to the usual 12,000. An extra 20% of patrols were also on standby, a spokeswoman said.