Amritsar, Aug 31 (IANS) A Pakistani prisoner Tuesday disappeared from a high-security jail in this Punjab city under mysterious circumstances, police said.

According to the police, the prisoner was identified as Nayamat Ali and he was arrested an year ago for illegally entering India in the Lopoke area near this holy Sikh city.

A jail official said that Ali had completed his term Friday and he was waiting for his release and repatriation home. However, the jail authorities were taken by surprise when they found Ali missing from the prison.

The authorities have launched an extensive search operation to trace him.

'We have suspended four wardens who were on duty for being negligent in their work. An inquiry has been initiated into the case and we have launched a massive search operation,' jail superintendent G.S. Sandhu, said.

According to the sources, Ali was last seen in his barrack Sunday afternoon.

'Ali was also not mentally stable. It is impossible for him to cross the 24-feet high boundary walls of the jail,' said a jail official.