According to an official statement from the London Marathon, the 29-year-old professional chef collapsed around the 36.2km mark (out of 42 km for the full marathon).
“Matt was a well-known chef who featured in Masterchef: The Professionals last year, inspiring viewers with his Nutritional Gastronomy movement and forward-thinking ideas. He was running for The Brathay Trust and in memory of his father, Martin, who died in the summer of 2016,” the statement read.
The sporting event included 40,000 participants and was hottest on record with temperatures reaching around 23 degrees, according to reports by the BBC.
Campbell shared a number of posts on social media in the lead up to the huge race, proudly posting a snap of his running wear and letting fans know that it was his second marathon in two weeks, having previously participated in the Manchester Marathon on earlier this month April 8.
Matt rose to fame after he competed on the cooking show in 2017.
Sending love to the young Chef's family and friends during this difficult time.