Iranian climber Elnaz Rekabi Friends have been unable to contact athlete since Sunday,
while embassy says she has returned home with rest of team.
The BBC also quoted “well-informed sources” as saying that Iranian climber Elnaz Rekabi passport and mobile phone had been confiscated.
BBC World Service presenter Rana Rahimpour tweeted on Tuesday morning that Iranian climber Elnaz Rekabi was on the plane to Tehran and that “there are concerns for her safety”.
Iranian climber Elnaz Rekabi competed in the Asian Championship.
Its organisers, the International Sport Climbing Federation, have been contacted for comment.
Online news site Iran Wire reported that Rekabi was taken to the Iranian embassy in Seoul to ensure he could fly home with minimal screening.