German prosecutors are investigating negligent manslaughter claims following the deaths of 19 people in a crowd crush at the Love Parade techno music festival.
Prosecutors' spokesman Rolf Haferkamp said investigations at Duisberg near Dusseldorf in northern Germany centre on suspicions of negligent manslaughter and negligent bodily harm.
The tragedy on Saturday - near a tunnel that was the only entrance to the festival grounds in the western industrial city of Duisburg - also injured 342 people.
It remains unclear what triggered the panic, but it appears that people trying to escape the surging crowd climbed up a metal stairway in front of the tunnel and then fell into the crowd and were trampled or crushed.
"The investigations are concentrating on the allegation of negligent manslaughter and negligent bodily harm," said Mr Haferkamp. "They are not directed against any concrete person at present."
A union representing German police has blamed organisers and officials in Duisburg. But witnesses also have pointed the finger at police and private security staff, saying the panic broke out after they closed one end of a tunnel - the only entrance - when the festival grounds became too full.
Police deny this, saying they opened a second exit to disperse the masses before the accident happened.
The daily Tageszeitung newspaper's sarcastic front-page headline summed up many Germans' reaction: "19 dead - No one was to blame." Berlin's B.Z. tabloid ran a picture of the officials under the headline "Parade of Failures."
One key question is whether the venue, an old freight railway station that local media estimated could handle 300,000 people, was suitable for the event.
German media reported that up to 1.4 million people showed up, although police suggested the figure was likely far lower given that the national railway brought 105,000 people to Duisburg by train in the preceding hours. Since the event was free, the number who attended may never be known.