BERLIN (Reuters) - A knife-wielding German teenager stabbed in a drunken frenzy at people leaving a ceremony to dedicate Berlin's new central rail station just before midnight on Friday and injured 28 before he was stopped.

Police said on Saturday six of those injured in the 10-minute long attack on a crowded street in the centre of Berlin were in serious condition but a victim initially on the critical list had improved.

The attack came as a shock to Germany less than two weeks before the World Cup soccer tournament opens and cast a shadow over the fireworks and celebrations to open the new station that some 500,000 people watched.

One of the first victims was HIV positive, police said, adding it could not be ruled out as a result that those stabbed after that person could also become infected.

"It was a horrible act," said Chancellor Angela Merkel, who had already left the station's gala ceremony. "It's good to know that the Berlin police caught the assailant so quickly."

The attacker was a 16-year old German from Neukoelln, a south Berlin district with a large immigrant population. Police said they were still investigating the motives of the attack by the student who has a police record for assault.

They said they were unsure what was behind the violence but ruled out a far-right link. They also said the teenager had acted on his own and was under the influence of alcohol. Police had noted him in a drunken state earlier outside the station.

"I've never experienced a crime like this in the seven years that I've been in this job," said Ehrhart Koerting, Berlin's interior minister in charge of the German capital's police department, at a news conference on Saturday.

"This sort of attack does not usually happen in Berlin or in Germany," he added, noting the youth was neither from a broken or troubled family. "It's horrifying to see how he developed. We need to think about violence in computer games and films."

QUICKLY ARRESTED

The attack occurred a few hundred metres from the showpiece rail station where Merkel and Berlin Mayor Klaus Wowereit had given speeches only hours before. A huge crowd had gathered outside the station to watch a concert and fireworks show.

As tens of thousands streamed away from the glass-covered, five-storey "Hauptbahnhof" after the show, police said the young man "ran amok" through the crowd on a street about three blocks to the east of the station.

"A crazy man ran down the street stabbing people arbitrarily," a police officer at the scene told Reuters.

The bloodbath took place along a long stretch of crowded sidewalks in the government quarter between the Reichstag parliament building and Charite hospital -- which probably saved the lives of some of the more seriously wounded.

Because one victim had the deadly HIV virus that causes AIDS, which can be spread via blood, police urged all those injured and released, as well as rescue workers who assisted the wounded, to report to authorities for urgent blood tests.

The teenager was quickly seized after witnesses pointed him out to security officials. Police said there were 60 witnesses. State prosecutors said he faced attempted murder charges.

Police said he knifed most of the people in the back and buttocks although some suffered chest and stomach wounds.

The stabbing, which follows a string of apparently racially motivated attacks on dark-skinned people in eastern Germany, may fuel concerns about security at the month-long soccer tournament.


It's a stormy world, we just live in it right ?