High school students worried about online threats by an 18-year-old prompted police to arrest the teen, who investigators say had a gun, ammunition and 117 names on what police termed a "hit list."

The Grade 12 student at Templeton Secondary School in Vancouver faces seven weapons-related charges.

Insp. Scott Thompson, in charge of youth services for the Vancouver Police, said officers found the hit list after they were contacted Friday evening by six students worried about the Facebook postings of a fellow student.

"It was reported that the male had a firearm and ammunition, as well as a hit list of staff and students at their high school," Thompson told a news conference.

Of the 117 names on the list, 71 were identified as staff and students, he said.

After interviewing the students who called police, officers arrested the teen suspect late Friday at his house.

Police say a shotgun, ammunition, a machete, a sword, a knife and two collapsible metal batons were seized from the teen's house, as well as a computer and other materials.

Thompson said the teen's name is not being released because while he is an adult now, some of the activity being investigated occurred while he was still a youth.

Although Thompson described the investigation as "one of the most serious" of its kind, students at the school appeared unfazed Monday.

Daniel Brown, 17 and in Grade 12, said his name was on the list.

"I'm not surprised," he said.

"We'd been talking and he said `By the way, you're number 25.' I asked him about it and he said that this is the number that you're on my list, basically that I'm going to kill you in."

Brown said the threat was made a couple of months ago and he originally thought it was a joke.

Police and school board officials are crediting the students for reporting the disturbing postings.

"When you examine other school-based incidents across North America, it's a very common pattern that the classmates of the individuals involved are aware that something is wrong," said Thompson.

"They dismiss those threats or concerns, they minimize them, they don't take them seriously. So our message has always been...that it's really important for students to come forward when they have information such as this."

Sarah England, 17 and also in Grade 12, said she didn't know the student arrested and didn't think her name was on the list.

England said none of the students she spoke to seemed to be panicking.

"I think everyone's pretty calm about it right now. They feel a bit nervous about what's happening."

She described the Facebook site as "pretty intense.

"There were pictures of guns and machetes," England said.

"I'm just really happy now that he is in custody and that someone actually told the police about this. . . before it could get out of hand."

While some students expressed shock at the arrest, others seemed more concerned with taking advantage of the warm, sunny day.

Minutes before Monday's dismissal bell rang, one group of students tossed a frisbee around the school grounds. Another played a game of softball nearby.

Some students stopped to chat with a police officer as they headed for home. Others stared curiously at the media throng that had assembled in the school's parking lot.

In 2006, an armed gunman burst into Dawson College in Montreal, killing one student and injuring about 20 others.

The gunman had earlier posted threats on an Internet site.

Chris Kelly, superintendent of schools for the Vancouver Board of Education, said the investigation has been "broad and it is intense."

He stressed that it was the combined efforts of police, staff, parents and students.

"Most significant for us is that we're standing before you today, describing a potential incident that didn't happen," he told the media Monday.

Police say there is now no immediate concerns for the safety of the staff, students and others at the school.

With files from The Canadian Press