Teen who killed 15 and himself described as a withdrawn youth

WINNENDEN, Germany — The psychological profile of a teenager who went on a shooting spree at his former school and killed 15 people and himself began to take shape Thursday, as investigators described a withdrawn young man from an intact family who broke off psychiatric treatment for depression.

But investigators faced a setback as they struggled to authenticate a chat-room posting that purportedly warned of a bloody rampage hours before Tim Kretschmer, 17, wreaked havoc on this quiet town near Stuttgart, southwest Germany.

He returned to his former high school on Wednesday to kill nine students and three teachers before fleeing on foot and by car, killing three more people and eventually turning a 9 mm Beretta pistol on himself after a shootout with police.

A joint statement released late Thursday by regional police and Stuttgart prosecutors said, "In the course of the afternoon, doubts arose about the veracity of the Internet chat."

A police spokesman said a search of Kretschmer's computer had shown no trace of his having made the posting.

A message posted Thursday to the site — Krautchan.net — said, "No killing spree was announced here." Prosecutors said they were trying to reach the U.S.-based provider of the site.

Across Germany, government buildings lowered their flags to half-staff Thursday, while schools held moments of silence for the victims.

In Winnenden, hundreds of people filed into a church in a drizzle after dark for a prayer service. A crowd of many more watched on a large video screen outside as a message of condolence from Pope Benedict XVI, a fellow German, was read aloud.

Throughout the day, students and residents paid homage to the dead outside the school, where they lit candles and laid flowers in a memorial.

Kristin Puengel, 14, said a friend of hers was among the eight girls killed. Three female teachers and a boy were also shot in the school. Three men were killed as Kretschmer fled police.

She said she knew Kretschmer by sight, but he was not a friend.

"He was somewhat withdrawn, but I would never have thought (he would be capable) of anything like this," Puengel said.

Authorities and friends said that although Kretschmer played table tennis and lifted weights, his main hobbies appeared to be shooting and spending hours on his computer — where investigators said they found pornographic films, violent games and a collection of horror and action films.

Officials said he had been interested in a girl about his own age, but that the feelings were apparently never reciprocated.

"It didn't work out," said Ralf Michelfelder, police chief in the nearby town of Waiblingen.

Kretschmer's father was a well-off businessman who legally owned 15 weapons and belonged to a gun club where his son regularly turned up for target practice, said Baden Wuerttemburg state Interior Minister Heribert Rech.