(ANSA) - Rome, August 30 - The most famed and infamous prison of ancient Rome was damaged Thursday when the roof of a central Roman church fell in.

No one was hurt because the church was, as usual, closed at the time of the accident. The vault of San Giuseppe dei Falegnami (St Joseph of the Carpenters), at the Roman forum, caved in, damaging the Mamertine Prison beneath it. The church is usually closed and only opened for weddings.

It was built between the end of the 16th century and the start of the 17th.

A fire-service crane has got rid of some remaining hanging parts of the caved-in roof. The wooden beams, which are still standing, are visible through the wreckage.

The inside of the church is full of broken beams and rubble, fire services said.

Sniffer dogs are going through the wreckage as a precaution, sources said.

The church's priest, who was in the building but not the church, is OK.

The collapse has damaged the once-infamous Mamertine Prison too.

"Some fragments of the roof," fire service engineer Luigi Liolli said, "hit a part of the altar.

"A beam then damaged the Mamertine Prison too", where the pavement gave way.

Colosseum Archeological Park Superintendent Alfonsina Russo told ANSA the church was the property of the Vatican's Vicariate of Rome.

She said the maintenance "is the competence of the Italian culture ministry, while the underlying Mamertine Prison is the competence of the Colosseum superintendecy".

The Mamertine Prison was used to house Rome's defeated enemies, many of whom were executed there.

Among those held there were Vercingetorix, leader of the Gauls during the Gallic War, who was executed at Caesar's Triumph in 46 BC; Jugurtha, King of Numidia, who died of starvation there in 104 BC; St Paul; and St. Peter, who was imprisoned there before being crucified, after performing baptisms in a spring at the bottom of the pit.

