"We will begin now," Bishop Klaus Küng told reporters after arriving in St. Pölten, where priests at the local seminary stand accused of having sex with students.

Küng, the bishop of Feldkirchen in eastern Austria, was appointed by Pope John Paul II to lead the probe on Tuesday.

The Vatican intervened a day after a 27-year-old Polish student priest was charged with possessing some 10,000 pornographic photographs.

Prosecutor Walter Nemec said many of the photographs showed sex with minors and the suspect faced up to six months in jail if convicted.

He said an inquiry would be held into two anonymous complaints of sexual harassment of minors targeting some priests at St. Pölten, where the director of the seminary and his deputy have already resigned.

Thousands of porn pictures on computers

Prosecutors had been investigating suspected child abuse at the seminary for several months but the allegations blew up into a national scandal last week when the magazine Profil ran pictures of seminary members groping each other.

The arch-conservative bishop of St. Pölten, Kurt Krenn, initially dismissed these activities as "pranks."

However when Profil also reported that police had found up to 40,000 pornographic images, including scenes of sex with children and animals, calls mounted for the bishop's dismissal.

On Tuesday Krenn (photo), who is also notorious for slamming Islam, welcomed the Pope's decision to order an investigation before leaving St. Pölten to go on holiday, the local news agency APA reported.

The scandal is the most sordid to hit the Catholic Church here since Cardinal Hans Hermann Groer was forced to resign from his Vienna archbishopric in 1995 over allegations he had molested young boys.

APA on Wednesday said the first whiff of scandal from St. Pölten came in October last year when a student at the seminary was found drowned in the Danube canal. The police at the time said they could not exclude foul play.