TOWIE Star's Sister Hands Back Marathon Medal
Natasha Argent was recorded as completing the 26.2 miles in three hours 44 minutes but it was soon noted that she had appeared to run the second half of the race faster than elite athletes.
Members of the public flagged up that her results showed her as running the final 20km in under an hour.Â
Earlier this week organisers of the event told Sky News the results were "extremely questionable".
Argent's results have now been wiped from the official London Marathon website.
Hugh Brasher, event director, said: "Our results team has been in touch with Natasha Argent, along with a small number of other runners, to request an explanation for the missing split times in her results from Sunday's Virgin Money London Marathon.
"At her request, we have removed her results from the system and she will be returning her finisher's medal to us."
Argent's results page showed she started Sunday's race at 10.16am and had completed the first 20kmÂ by 12.33pm.
However, her timings for the next 20kmÂ were not visible on the site.
She then reappeared at the 40km mark at 1.21pm and finished at 2pm.
Organisers said there are a number of suspect times every year and around 20 out of 39,000 entrants are being investigated this year.
James Argent completed the London Marathon in 2012 with a time of just over six hours.
On Sunday he congratulated his sister on Twitter for her achievement but the tweet was later deleted.
Sky News has contacted his representative for a comment.