An ex-priest who lives in Britain has been given a 12-month suspended sentence after ambushing the front-runner in the men's marathon in Athens.
The protester is led away by security guards
Cornelius Horan, 57, originally from County Kerry in the Irish Republic but living in London, was freed but it is unclear if he has been deported.
Horan, who pushed Brazil's Vanderlei De Lima off the road, told police it was to "prepare for the second coming".
De Lima eventually took bronze while Italy's Stefano Baldini took the gold.
Mebrahtom Keflezighi of the United States took silver.
The Brazilian Olympic Committee plans to lodge an appeal against the result of Sunday's marathon because of Horan's actions.
Horan, who was wearing a kilt and green beret, was arrested and taken to the General Police Division in Attica and held overnight.
Police said Horan had mental problems, adding he was "not very well".
A police spokeswoman said: "Religious obsession is being deemed as the cause of his actions."
It was not the first stunt by the former priest, who last year disrupted the Silverstone Grand Prix by running across the track.
Following that incident, he was given a two-month jail sentence for aggravated trespass.
Leslie Broad, of Deunant books, a publisher of electronic books which has published Horan's works on biblical prophecies, said: "He comes across as a shy, very intelligent and compassionate man but as is often the way with people who are very intelligent, it sometimes manifests itself in very strange ways."
After the incident, De Lima said he was "happy" to win the bronze but following the medal presentation he said: "If it were not for that lunatic, I am sure I would have won the gold.
"For the way I was running, I was unstoppable."
He said the protester did not injure him, but broke his rhythm and he lost concentration.
After the race, the International Olympic Committee said it was saddened by the incident and awarded de Lima the Pierre de Coubertin Medal at the closing ceremony.
An IOC spokesman said: "We decided to do this in recognition of de Lima's exceptional demonstration of fair play and Olympic values during this evening's marathon."
The IAAF also confirmed that the overall marathon result would not be changed despite the incident.