Athens - Four prison guards and a pilot were charged on Tuesday with negligence, after two of the country's most notorious criminals escaped from a maximum security 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.

Greek government officials charged four prison guards at Athens' Korydallos prison and the pilot of the helicopter for failing to prevent the escape and are expected to appear in a Greek court later Tuesday.

Officials have ordered the freezing of all bank accounts of prison employees and have suspended nine prison guards over the jailbreak, which has embarrassed the ruling conservative government.

There has been no trace of the two fugitives following a nationwide manhunt.

Both Palaiokostas and Rizal 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)