WINNENDEN , Germany ( CNN ) -- Students jumped out of windows and locked themselves in classrooms as a former pupil rampaged through a German school with a gun , killing at least a dozen people there Wednesday , a student at the school told CNN . People lay flowers at the school Wednesday . `` Suddenly there were police standing in front of me and told us to run outside quickly , '' Luisa Santonastaso , 16 , said . `` At first we did n't know what to do . So first we went to the class and picked up some of our classmates and ran out . `` Then we heard that someone was inside shooting . Then we also saw a teacher who had blood on his hands because he wanted to help a female teacher who sacrificed herself for a student -- she stood in front of a student to protect her , '' the girl told CNN by phone from Germany . `` The guy just entered the classroom and started shooting and a friend of mine was panicking so much that she jumped out of a window . I think she broke her arm . She 's in hospital now . '' Santonastaso 's friend was not the only one who jumped , she said . Dressed in military gear , the gunman -- identified by police as Tim Kretschmer , 17 -- killed a total of 15 people in two different towns before he died . Watch more about the shootings » . Initial indications are that he shot himself , but police are continuing to investigate , said Erwin Hetger , the regional chief of police . The rampage in Winnenden , a small town about 20 kilometers ( 12 miles ) northeast of Stuttgart , and spread to neighboring Wendlingen . As people at Albertville-Realschule Winnenden school -- where Kretschmer used to be a student -- realized what was happening , many burst into tears , Santonastaso said . `` Everybody was crying because nobody could really imagine what had just happened . They brought us to the swimming pool hall in Winnenden for security reasons , '' she said . `` Then all our parents were called because no child was allowed to leave without parents , '' she continued . At least one parent got awful news when she arrived . `` One mother came and the teachers had to tell her that her child had been injured or shot dead , and then she cried really hard and fainted , '' Santonastaso said . iReport.com : Town in shock over shooting . Santonastaso 's own parents were more fortunate . `` When I first called to tell them what had happened they wanted to come right away , but I told them that was n't possible because we were being brought to somewhere safe , '' she said . Later , she said : `` My parents and my friend came and we went out with them . Out there it got a bit better . '' CNN 's Marco Woldt and Lianne Turner contributed to this report .
Student tells how classes turned to horror at hands of rampaging gunman . She says two teacher shot when she put herself between the gunman and a student . Students jumped from windows to escape killer . Gunman killed one people in one German towns near Winnenden .