However, he did not fly home to Ireland, Pol Sen Sgt Maj Jirawat Nawatong of the Tourist Police, told The Phuket News. Instead, Mr O'Brien flew out to stay in Malaysia with a relative.
After he was found wandering with minimal memories in Thalang, he was taken to the police station there. However, the station was at that time under siege from anti-government protesters.
Rather than risk having Mr O'Brien involved, and deciding that there was actually nothing wrong with him, the Tourist Police dropped him off in Patong - and lost sight of him.
He next appeared at the airport and was once again taken in hand by the Tourist Police. Finally, with the help of Irish Honorary Consul Helene Fallon-Wood, police learned of the relative, whom they contacted.
On Thursday he flew out of the island.