An inmate of Phitsanulok Prison, whose photograph was taken inside the prison and posted on Facebook, has been transferred to an isolation cell.
BOUND FOR GLORY: Marwin on Facebook
The inmate, Marwin Samphanwong, 28, had pictures of him in chains displayed on a Facebook account registered under the name "Winner and Khun Noo Mayom". Marwin had been convicted of rape and was serving a five-year jail term which will end on Nov 1.
Phongmit Prasertsakul, the prison's commander, said 30 warders searched the sleeping quarters of the inmate and found nothing illegal.
However, while searching elsewhere, they found a suspicious package left on the side of the entrance to the residence of the prison commander, which is adjacent to the prison.
The package, carefully bound by tape, contained seven mobile phones, four extra batteries and four chargers. Mr Phongmit said the package was hidden in preparation for being thrown into the prison at night.
The Facebook pictures, one of which shows Marwin shackled at the ankles and squatting beside a prison locker, were believed to have been taken with a mobile phone camera. Mobile phones are banned in the prison.
Mr Phongmit said Marwin claimed he had borrowed a friend's phone to take the photo.
A search of the jail failed to locate the phone and further investigations are under way.
The prison chief said Marwin's jail term would be extended by one to two years for the incident.
He insisted the prison has in place strict measures to prevent the smuggling of communication devices.
These include putting up a large net around the compound to prevent any device from being thrown over the prison walls.
A source at the prison said smartphones are sold among inmates for upwards of 100,000 baht - iPhones sell for 170,000 baht each.
The Facebook page has several photos of prisoners, causing red faces at the warden's office.