Westminster Police Department spokeswoman Cheri Spottke said she didn't know if the student made any threats or statements before starting the fire at Standley Lake High School in Westminster, northwest of Denver. He was taken to a hospital with unknown injuries.
Spottke said the fire was contained to the cafeteria and was put out by an adult with a fire extinguisher. There also was extensive smoke in the building.
Jefferson County Public Schools spokeswoman Lynn Setzer says Standley Lake High has been closed for the day and students were sent home. She said she did not know if students were in class when the fire was reported at about 7:15 a.m.
No additional details about the injured student or the fire's cause were released.
"Our focus now is making sure the kids are safe," Spottke said.
Setzer said students without cars were being taken by buses to a local middle school, where they could be picked up by their parents.
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