Athens - The Greek government ordered the freezing of all bank accounts of prison employees on Monday, after the embarrassment of seeing two of the country's most notorious criminals bust out of prison by helicopter - for a second time.

On Sunday kidnapper and armed robber Vassilis Palaiokostas and Albanian criminal Alket Rizal absconded from Athens' highest security jail by helicopter, in a repeat of an identical 2006 escape.

The two men, who had been in solitary detention but exercised in the same area, were smuggled out after a helicopter landed on the jail's roof and dropping them a rope ladder to lift them away.

The helicopter was reportedly later found abandoned by a main highway near Athens.

Government officials ordered that all bank accounts of prison employees be frozen while the prime minister has called an emergency meeting Monday.

Both men had escaped from the same prison when a hijacked helicopter landed at the Korydallos prison's central yard during exercise time three years ago.

At the time, the guards had failed to react because they thought it was a visit by government officials.

The architect of that escape, Palaiokostas' brother Nikos, has since been captured and jailed, and is now likely to face increased security.

Vassilis Palaiokostas, 43, was serving a 25-year sentence for the kidnapping of a Greek businessman. The other escaped prisoner, Rizai, 35, was serving a life sentence for manslaughter. (dpa)