Students were seen jumping from the school windows, witnesses say
Witnesses have been describing their horror after a teenage gunman went on a rampage at a secondary school, leaving at least 15 people dead.
One was quoted as saying the killer "sprayed bullets" around and a journalist said he used a machine gun.
Police chief Erwin Hetger said the teenager "carried out a bloodbath" the like of which he had never seen.
Mr Hetger told the BBC of the heartbreak of breaking the news to the families of the dead.
"Of course our thoughts are concentrated on the parents. I have looked some of them in the eye, and it's damn hard to keep your composure," he said.
"I've been president of police in Baden-Wuerttemberg for 19 years now, and I can't remember a deed as terrible as this," he also told Reuters news agency.
Some students were seen jumping from school windows after the gunman opened fire, and parents quickly gathered around the school, the Associated Press reported.
The mother of one such student said: "What can I say? I find... I don't understand the world anymore.
"I'm sorry. My daughter was there when it happened. She's sitting at home now trembling and crying.
"She and her friend jumped out of the window. Her friend is now in hospital ... We hope that she's all right.
"I can't take any more ... I thought this sort of thing only happened in America. But it seems that America has come to Germany."
Local reporter Robin Szuttor said the attack at Albertville secondary school in Winnenden, south-west Germany had "destroyed this idyllic place".
Speaking to the BBC from the scene, he said: "Well it was a horrible situation, there was a mother who was crying because she didn't know if her son was alive.
"There was another mother who heard from another student that her daughter is alive. All the people are full of hope but they don't know really what happened.
"They are very nervous here and very very sad."
The chief reporter from the Stuttgart Journal newspaper, Kevin Latzel, told the BBC: "Oh, it's very horrible, there's a lot of hectic [sic] and the parents are crying, the pupils are crying and a lot of police is there.
"They are very afraid, the pupils are calling their parents and the parents they want to pick it [them] up but they can't do this, the parents they are not allowed to get into the classrooms.
"We know that he's a 17-year-old boy from a neighbouring village from Winnenden and his parents had a gun and then he came in the morning at the school and shot around."
Roberto Seifert, who works at a company next to the school, said police activity was constant.
"Police are coming through the whole time, he told Reuters.
"They're obviously looking all over town for him... we've never had anything like this."