Around half of the 2,000 athletes taking part in the Original Mountain Marathon in the Lake District were last night thought to be stranded in the hills, as rescue teams continued to battle against the storms.

Police said around 840 people had taken shelter in four locations in the area, including a school and a barn, while 45 runners were reported to be sheltering inside Honister Slate Mine, which sits on top of one of England's steepest mountain passes. It was last night reported that not all participants had been accounted for.

Rescue operations have been severely impeded by the extreme conditions, with storm-force winds ruling out the use of RAF helicopters, and a lack of mobile phone reception in the hills making it difficult to locate runners. There have been reports of a number of participants being taken to hospital suffering from hypothermia and other injuries.

Mark Weir, who owns the Honister Slate Mine, said race organisers had ignored advice to call off the two-day event. He said: "I believe there were up to about 2,000 people who entered this race and I advised the organisers not to go ahead with the event."

He added: "We have had people coming in throughout the day in pretty bad states. They are dripping wet through and very cold.

"Our staff are helping to transport them off the mountain pass and down to Cockermouth where the emergency services are taking over. But we need more help and more buses as there are still plenty of people up here."

None of the race organisers were last night available for comment.

In Scotland, winds of up to 100mph lashed the country and torrential rain caused flooding and traffic chaos. Coastguards were on alert as storm-force winds led to treacherous conditions at sea, while high winds brought down trees across the country, closing roads and causing chaos for motorists.

Five flood warnings were put in place, with concerns raised over the River Spey from Spey Dam to Loch Insh, the River Tay from Kenmore towards Dunkeld, as well as the River Lyon and River Earn, while the Scottish Environment Protection Agency issued a further 15 flood watches covering much of the country.

Gusts of up to 68mph were recorded in Aberdeenshire and 58mph in Edinburgh, and police forces reported trees felled by storms, including one in Edinburgh's Queen Street.

On Aberdeen's Guild Street, falling masonry caused by high winds left one person injured, while residents of the Maragowan caravan park in Killin, Perthshire, had to be evacuated.

Meanwhile, an 80-year-old woman had to be led by firefighters from her flooded home in Glendevon.

Lifeboat crews in Shetland were also called into action in hurricane-force conditions after a fishing boat ran aground.

The boat, with a four-man crew, ran into difficulties as winds rose to 100mph off the coast of Unst. Rescue crews also reported last night that a Russian refrigerated cargo ship was in difficulty 20 miles south of the island of Foula, apparently suffering from engine trouble and stranded in storm-force winds.

Elsewhere, ferry sailings were disrupted, with Caledonian MacBrayne and NorthLink cancelling several services, and the Tay and Forth road bridges left open to cars and single-decker buses only.

Violent winds were exacerbated by torrential rain in many parts of the country, with several police forces reporting "extremely hazardous" amounts of surface water on roads. Lothian and Borders police were last night urging motorists to take extreme care on stretches of the M9 in particular, while in Dumfries and Galloway the A708 near Craigieburn Hill, Moffat, was closed after torrential downpours left the road submerged under two feet of water.

The Met Office confirmed that the bad weather is set to continue throughout the week, with temperatures expected to plummet below freezing and up to 15cm of snow expected in some areas.

The Met Office said the cold weather, which coincides with the end of British Summer Time and the clocks going back one hour, would be more severe than expected for the end of October.

A spokesman said: "It's unusually cold for this time of year – at sea level and in the conurbations it will probably be about 2°C or 3°C during the day, and down to -1°C at night."

He added that the cold weather would hit Scotland tomorrow night and continue on Tuesday and Wednesday.