NIWOT, Colo. -- Niwot High School has been released from lockout and has resumed normal operations, according to the school's website.
The school was placed on lockdown Tuesday morning because of a rumor that a student had brought a gun to school, according to the Boulder County Sheriff's Office.
Deputies said they locked down the school and searched the school.
A short time later, the school was moved from lockdown status to lockout.
The school's website said, "The building has been secured, all students are safe in their classrooms."
At 10:39 a.m., the school said it had lifted the lockout and resumed normal operations.
The Boulder County Sheriff's Office said no credible threat was identified, but law enforcement would remain as operations returned to normal.
Lockdown & lockout at Niwot HS lifted at 10:35. No credible threat ID'd. Law enforcement will remain as school operations return to normal.
— BoulderCountySheriff (@BldrCOSheriff) November 15, 2016
Niwot High School is located 35 miles northwest of Denver. It has 1,290 students in grades 9-12.