German police said they thwarted a plot by a pair of teens to attack their school in Cologne.
Police were notified of the plot after classmates saw the pair studying pictures of the Columbine school shooting and alerted their principal.
One of the teens died after throwing himself in front of a tram after being questioned by police officers on Friday, lead investigator Norbert Wagner said on Sunday.
The other teen, an 18-year-old, was arrested by police in Cologne and confessed to the plot, Wagner told reporters at a news conference.
Neither teen was identified. Officers said they believed the pair had planned to storm the school with two crossbows and two air guns that officers discovered during a search of the two suspects' homes. Police also said they might have intended to use molotov cocktails or pipe bombs.
"They wanted to hurt and kill people and then take their own lives," Wagner said of the two 12th-graders.
Wagner said the principal of the Georg-Buechner high school in Cologne contacted authorities on Friday, after classmates had observed the 17-year-old studying an Internet page with pictures of the Columbine massacre.
Investigator: Police find list of teachers, students
During a search of their homes police also found a list of names of teachers and students who were possibly to be targeted by the pair, Wagner said.
Wagner said police had found no evidence of a clear motive for the attack, although he noted the 18-year-old was considered a loner by his peers and had been struggling in school. The 17-year-old, however, did not appear to have any troubles, he said.
The pair appeared to be planning to carry out the attack on the coming Tuesday — the first anniversary of Germany's most recent school shooting, Wagner said.
Last Nov. 20, Sebastian Bosse, 18, opened fire at his former school in Emsdetten before killing himself. Five people were wounded and dozens injured.
After the shooting, officers found a diary by Bosse in which he also referred to the 1999 massacre at Columbine High School in Littleton, Colorado, when Eric Harris and Dylan Klebold killed 12 students and a teacher, and wounded 23 others.
Earlier this month, an 18-year-old student killed eight people and himself at a school in southern Finland. He had also referenced the massacre at Columbine.