VATICAN CITY (Reuters) - Pope John Paul has performed three exorcisms during his 23-year pontificate, including one as recently as September, one of the Catholic Church's leading exorcists said on Monday.

Father Gabriele Amorth told Italy's La Stampa newspaper that the Pope had carried out his first exorcism in 1982.

"This girl was rolling around on the ground. People in the Vatican had never seen anything like it. For us exorcists it is run of the mill," Amorth said.

The Pope has since taken part in two more exorcisms, including that of a 20-year-old woman in September, to underline the importance of the ceremony.

"He carried out these exorcisms because he wanted to give a powerful example. He wanted to give the message that we must once again start exorcising those who are possessed by demons," Amorth said.

For Roman Catholics, exorcism is the casting out of what is believed to be an evil spirit through prayer and the laying on of hands. Amorth said possession by demons took many shapes.

"I have seen many strange things...objects such as nails spat out. The devil told a woman that he would make her spit out a transistor radio and lo and behold she started spitting out bits and pieces of a radio transistor," he said.

"I have seen levitations, and a force that needed six or eight men to hold the person still. Such things are rare, but they happen," he said.

Amorth said the woman whom the Pope exorcised in September was still undergoing treatment.

"It's a very serious case. A series of curses," he said.

The interview was published a day after the Pope warned of the daily temptations of the devil during his Sunday address.

"The devil, the 'prince of this world', even today continues his insidious actions. Each and every man...is tempted by the devil when he least expects it," the Pope said.

The official Roman Catholic exorcism starts with prayers, the blessing and sprinkling of holy water, the laying of hands on the possessed, and the making of the sign of the cross.

It ends with the priest commanding the devil to leave the possessed person.