The organisers of Belfast marathon have apologised to its competitors after admitting the route was mistakenly extended.
Participants ran an extra 0.3 miles more than they should have.
It was blamed on human error after the lead car diverted from the official route.
In a statement, chairman of the Belfast Marathon Organising Committee David Seaton said: "On behalf of the organising committee, we would like to apologise to competitors of today's race.
"Approximately 460 additional metres were added to the officially measured course of 26.2 miles.
Massive congratulations to all our winners today! Top Male 🥇Joel Kositany 2.18.41 🥈Eric Koech 🥉Bernard Rotich 2.18.55 Top Female 🥇Caroline Jepchirchir 2.36.38 "fastest ever finish by a woman in Belfast" 🥈Shewaye Wolde Meskel 2.37.34 🥉Vira Ovcharuk 2.38.59 pic.twitter.com/n9ZOq7cJuS — BelfastCityMarathon (@marathonbcm) May 5, 2019
"This was due to human error, with the lead car diverting from the official route.
"I can assure all participants that protocols will be put in place to ensure this never happens again.
"In the meantime, we are in the process of adjusting runners times to reflect the correct distance.
"Feedback on the new route has been overwhelmingly positive and we thank the thousands of spectators who lined the route to support 18,000 runners, walkers and wheelchair athletics."
It comes after Kenyan runner Caroline Jepchirchir ran the fastest ever women's time in Belfast.
She crossed the finishing line after 2:36:38 smashing the record in the city.
The course this year was changed to a faster and flatter route, organisers said.
Around 5,000 people took on the new marathon route, which is an increase of 60% compared to last year.
More than 18,000 participants took part in the event, which was held on Sunday for the first time.
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