A 36-year-old man from the southeast of England has died after collapsing near the end of the London Marathon.
Organisers said he received immediate treatment between mile 23 and 24 and that an ambulance arrived within three minutes, but he died later in hospital.
The man was from southeast England and no further details will be released as the family have asked for privacy.
The cause of death will be established later through medical examination.
Organisers of the event said in a statement:
"Everyone involved in the organisation of the London Marathon would like to express sincere condolences to his family and friends."
More than 40,000 runners competed in Sunday's event.
Kenyan Amos Kipruto won the men's race in 2:04:39, while Ethiopian Yalemzerf Yehualaw was the fastest woman in 2:17.25.
Thousands lined the 26.2-mile route to cheer on the elite athletes and the masses of amateur runners who raise money for charity.
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