Records tumbled in the sweltering heat of the 2018 London Marathon, as Sir Mo Farah, wheelchair athlete David Weir and Mother Nature all made historic contributions to the showpiece event.

An exhausted Sir Mo broke the marathon record by a British athlete as he finished third in the men’s race, despite an initial 11-second discrepancy between the two official times.

The 35-year-old multiple Olympic and world gold medallist struggled with the pace, hot conditions and water bottle mix-ups, but still beat Steve Jones’s 33-year-old record with a time – ratified more than an hour after crossing the finishing line – of two hours, six minutes and 21 seconds.

2018 Virgin Money London Marathon
Sir Mo Farah poses for a photo with Prince Harry after finishing third (Paul Harding/PA)

Race organisers had previously urged runners to reconsider aiming for personal bests and suggested ditching fancy dress costumes ahead of what proved to be the hottest ever London Marathon.

Runners were seen to collapse in the heat – amplified by the tarmac and thousands of bodies – with one even stretchered across the finish line by medical staff.

Around four-and-a-half litres of water was distributed per person – the most of any mass participation event in the world, organisers said, adding that water even ran out on miles eight, nine and 10.

2018 Virgin Money London Marathon
A runner is stretchered across the line by medical staff (Paul Harding/PA)

Racers were cooled off by extra ice, water and run-through shower stations dotted along the 26.2-mile route, which snakes along both sides of the Thames.

Meanwhile, almost 100 runners lined up to attempt Guinness World Records – dressed variously in suits of armour, as mythical creatures and wearing stilts and ski boots.

Rob Pope ran a record time for a runner dressed as a film star, crossing the line dressed as Forrest Gump in just over 2 hours 36 minutes.

The 39-year-old, from Liverpool, who has run more than 15,000 miles in an attempt to emulate the character from the 1994 Tom Hanks movie, said: “I can run like the wind blows.

“Today was unbelievable. I had so many ‘Run Forrest run’ shouts – a couple of ‘beardy man’ and a couple ‘Jesus’ but mostly Forrest Gump!”

2018 Virgin Money London Marathon
Runners use showers to cool off (John Stillwell/PA)

The first fire crew on the scene of the Grenfell Tower disaster raised more than £41,000 for children affected by the inferno, while a police officer knifed five times in the London Bridge attack also finished, raising money for the hospital that saved his life.

Women’s sport trailblazer Kathrine Switzer, 71, who made history in 1967 by competing in the then men-only Boston Marathon, also completed the course.

The Met Office posted highs of 23.2C (73.8F) – beating the previous best of 22.7C (72.8F) set in 1996.

Elsewhere on the track, six-time Paralympic gold medallist Weir won the men’s wheelchair race for an unprecedented eighth time.

And Lily Partridge was the first British woman over the line in the elite women’s race, with a time of under two-and-a-half hours.

2018 Virgin Money London Marathon
Great Britain’s Lily Partridge completes the Women’s Marathon (Paul Harding/PA)

Sir Mo said he would spend time with his family after not seeing his children due to a strict training regime in Ethiopia during the last three months.

He said: “It slowed down after halfway, from there you pay the price, you can’t go off that fast and come away with 2.02.

“It was a hard way to run the pace because we were set for the world record pace at the beginning…

“I know I can go at least 2.04, 2.05, in an even-paced race, today it was the hardest way to run in any race. But at the end of the day you’ve got to fight like a man.”

Eliud Kipchoge of Kenya won the men’s race in a time of two hours, four minutes and 16 seconds, while compatriot Vivian Cheruiyot won the women’s race in a time of two hours, 18 minutes and 31 seconds.

Those not competing in the elite races received a royal send-off as the Queen pushed the event’s start button, sending thousands of competitors pounding through the capital’s streets.

The Queen with Sir John Spurling, chairman of London Marathon Events Ltd, before she pressed a button in Windsor Castle, Berkshire to start the London Marathon (Chris Jackson/PA)
The Queen with Sir John Spurling, chairman of London Marathon Events Ltd, before she pressed a button in Windsor Castle, Berkshire to start the London Marathon (Chris Jackson/PA)

More than 40,000 marathon runners then proceeded to follow hot on their heels.

Last year, the event raised £61.5 million for charity, a world record for an annual one-day fundraising event, making the total raised since 1981 around £890 million, organisers said.

A record 386,050 people applied for this year’s race – almost a third more than last year and the highest number for any marathon in the world.