Police are looking to trace a female athlete who has not been seen since finishing this weekend's London Marathon in 20th place.
Mami Konneh Lahun, 24, from Sierra Leone had been staying at an address in Greenwich since arriving in the UK on April 7.
She was due to fly home later today but did not return to her temporary accommodation after yesterday's race.
Mami has no known links to the UK.
More top news
The robbers casually approached their victim on a busy high street before before spraying a noxious substance in his face.
Tencho Hristov ignored warnings and got trapped between barriers at Roydon in Essex.
The 6km bike track will include 130m of the South Circular near Kew Bridge.