Oxford's Mara Yamauchi was forced to pull out of the Olympic marathon after less than 10 kilometres after suffering from a bruised ankle.
She tearfully stopped at the side of the road 9.4km into the race after deciding she could not go any further.
Britain's medal hope Paula Radcliffe was forced to withdraw with a foot injury earlier in the week. The race was won by Ethiopian's Tiki Gelana.
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The Bishop of Salisbury has called the attack on Segei Skripal and his daughter Yulia "a violation of our community."
Thursday night's weather for the west of the region
Thursday night's weather for the east of the region