Vienna, Austria ? An official with the Archdiocese of Vienna urged the Vatican on Wednesday to oust a Roman Catholic bishop in charge of a seminary where candidates for the priesthood hoarded child pornography and photos of themselves kissing and fondling each other.

The cleric, Bishop Kurt Krenn, dismissed the photos as part of a “schoolboy prank” and accused critics of exaggerating the case — the worst church scandal in Austria since allegations of pedophilia brought down a cardinal nearly a decade ago.

Police examined hard drives on computers seized at the seminary in St. Poelten, 50 miles west of Vienna, as part of a child pornography investigation.

Officials said the discs contained some 40,000 photographs and numerous videos, including child pornography and photos of young seminarians kissing and fondling each other and their older instructors and engaging in sex games.

As some of the photos began appearing in Austrian newsmagazines — depicting students in sexual situations while clad in black shirts and priestly collars — calls mounted for Krenn to resign.

Only if Krenn steps down “will an extensive investigation be possible,” said Helmut Schueller, the Vienna Archdiocese’s ombudsman for victims of sexual abuse.

The seminary’s director, the Rev. Ulrich Kuechl, already has resigned along with his deputy, Wolfgang Rothe.

But Krenn, 68, refused to step down and rebuffed his critics.

In a nationally televised interview, he conceded overall responsibility for the seminary, but he rebuked the national bishops conference for pressing for his resignation and said the furor was overblown.

“Although these things naturally fall into my competence, I had nothing to do with them,” he said.

Krenn’s spokesman, Michael Dinhobl, told the Austria Press Agency the bishop launched his own investigation Wednesday. The internal probe by a six-member committee was an attempt “to examine the allegations … in the light of church morals and canon law,” Dinhobl said.

The Vatican, which condemns homosexuality, has refused to comment.