Eleven inmates escaped a prison in central Greece during exchange of fire with guards in Friday night, which has left two prison guards injured, one of them in serious condition, Greek authorities announced on Saturday.

Following a count down of prisoners at Trikala's complex after the standoff with the passengers of two trucks who attacked the prison's entrance with automatic weapons, police discovered that eleven foreign nationals, convicted for robberies, were missing.

According to an official announcement by the Justice Ministry in Athens, no weapons were discovered inside the prison.

As a manhunt is under way since the early hours of Saturday, according to yet unconfirmed local media reports, at least two inmates have been tracked down and arrested.

Friday's incident is the latest prison break attempt in a month in Greece. On February 24, a notorious Greek gang boss who serves life imprisonment failed to escape from the same prison with helicopter and was injured by gunfire.

Last weekend, another notorious convict in Greece, Albanian national Alket Rizaj, held prison guards as hostages for several hours before surrendering to police.