The areas affected include Voe and Brae in the north mainland along with the islands of Yell, Unst and Whalsay with the majority of faults a result of snow and ice sticking to overhead power lines, causing them to fail.

As of 11am on Tuesday, power had been restored power to more than 2,500 properties, with 3,800 homes still off supply in Voe, Whalsay, Brae, Tumblin, Yell and Unst, Scottish and Southern Electricity Networks (SSEN) said.

SSEN warned that it may take until the end of the week to restore power to all customers due to the extent of damage, significant travel restrictions and continued issues accessing fault locations.

Mark Macdonald, Head of Region at SSEN Distribution, said engineers have been out since first light working to reconnect people.

He said: “We’ve seen extensive damage to the overhead power lines connecting homes and businesses, including multiple points of damage caused by snow and ice accretion which was not forecast. Our local teams have described the conditions as the worst they’ve seen in over 20 years.

Mr Macdonald added: “I’d like to reassure our customers we’re doing everything we can to restore power as quickly as possible and would encourage anyone who may be in a vulnerable situation to contact us on the power cut helpline, 105.”

All schools in Shetland were closed on Tuesday due to the weather conditions, while several schools were closed in Aberdeenshire.

Scotland has been hit with some severe winter weather

Police in Shetland urged people to take care if they have to venture out.

Inspector Sam Greshon said: “With adverse weather expected to continue today, consider travelling only if you have to.

“Leave extra time for essential journeys and take warm clothes, food and water in case of any delays.

“Take a mobile phone with you and check it is fully charged.”

A Met Office yellow weather warning for snow and ice, Scotland’s longest on record, remains in place across the north of Scotland, Shetland and Orkney until midday on Thursday, with forecasts showing more winter weather forecast.

Scores of schools across the country have been forced to close for a second day due to the cold weather.

Graeme Keddie, of SSE Networks, told BBC Radio's Good Morning Scotland the network in Shetland had been damaged by extreme weather on Monday afternoon and evening.

"We've reconnected about 2,000 homes across Shetland but around 3,800 remain without power. Some of them were connected last night but further damage has been reported." he said.

"Our teams are doing all they can to restore power as quickly as possible. At first light our teams will be out assessing the damage and looking to mobilise operations as quickly as possible."

The temperature dropped to -17.3C in Braemar, Aberdeenshire, -15 in Balmoral and -14 in Aviemore -13C at Dalwhinne and at Fyvie Castle it was -12C in the coldest night of the year so far.

The RAC experienced its biggest day for breakdowns on record, with around 12,000 drivers needing help.

RAC Breakdown’s Rod Dennis said: “Yesterday was officially our busiest day for breakdowns on record, with around 12,000 drivers needing help, the equivalent of eight every minute of the day. Even our busiest day during the infamous Beast from the East in 2018 didn’t see as many people breaking down.

“We believe two key ingredients have combined to create the worst-ever winter breakdown cocktail – a sustained period of cold weather with an absence of widespread snow that would otherwise keep people indoors, and a big rise in the number of drivers who can’t afford to maintain their vehicles as well as they’d like to due to the pandemic and the cost-of-living crisis.

“Today remains an incredibly demanding day for our patrols, with the rail strikes likely to force yet more people onto the roads.”

Scotland's weather: Shetland homes without power as temperature of minus 17 recorded in Braemar in coldest night of year