A man has been arrested after the Geneva Arena was evacuated on Saturday night just before a concert by the French rapper Lomepal was due to start.
The concert was a sell out with 8,500 fans.
Police say the man is being detained – charged with making threats to alarm the population. They say he has jihadist links.
The venue was searched late into the night. But there are no reports of any device found.
The crowd were asked to leave the building and make their way home. Police say the atmosphere was calm.