In this photograph, Indian runner Samir Singh drinks water after his morning run in Mumbai.

An ultra marathon runner who set himself the task of running 10,000km in 100 days in the scorching Mumbai heat has collapsed with exhaustion just 36km short of his goal.

Samir Singh, dubbed “The Faith Runner”, spent nearly three months running between Mumbai’s slums and business district using donated clothes and equipment and living on just £2.30 a day.

After ending his attempt on Sunday, the 5ft 7in running coach weighed just 88lbs (40kg) having suffered with stomach problems and viral fever.

Mr Singh began his challenge on 29 April and has been running through monsoon rains without missing a day.

He needed to run 150km (93 miles) on the final day to reach his target after falling behind schedule through illness.

But the 44-year-old was forced to stop agonisingly short of his goal after completing 114km (70 miles) on Sunday.

The 44-year-old battled through scorching temperatures and monsoon rains during his challenge

The 44-year-old battled scorching temperatures and monsoon rains during his challenge

Vikram Bhatti, who ran his campaign, said: “He was plagued by gastro-intestinal infections and contracted viral fever but has run 9,964km in 100 days.”

Ahead of his final run, Mr Singh had said: “My journey of running 100 kilometres per day is very challenging but I wanted to show the endurance limit of human spirit.

“I survived without a job for the last nine months and people have come forward and supported me with donations, shoes, clothes and equipment.”

The five-time ultra-marathon winner lost 35lbs during his challenge and his ordeal captured the imagination of documentary makers who christened him “The Faith Runner”.

Fans also joined him for several stretches of his run every day, similar to Tom Hanks’ character in the Oscar-winning Forrest Gump.

But Mr Singh plans to hit the road again after he has recovered, this time running 40,000km.

He said: “I have not met my mother for a while as she would be heartbroken looking at my sunken face.

“But I am happy so many people are invested in my story right now.”