Police determined a bomb threat to the University of Colorado Boulder campus on Friday was false after it had forced evacuations of three buildings.

At 1:14 p.m., evacuations were lifted Norlin Library, the Ketchum Arts and Sciences building and the Ramaley Biology building, according to a social media post from the University of Colorado Boulder Police Department.

Norlin Library remained closed for the remainder of the day, and classes continued in the Ketchum and Ramaley buildings.

CUPD said officers would escort students into Norlin to retrieve their belongings.

University police dispatch received an unconfirmed bomb threat regarding Norlin Library at 11:20 a.m. and subsequently evacuated the library and the two nearby buildings, according to the university.

At approximately noon, university police and K-9 units responded to the scene and advised people to avoid the area. No other buildings were evacuated, and classes in all other buildings remained on schedule, according to university police.

Boulder Police officers and Boulder Fire-Rescue crews did not respond, according to spokespeople Dionne Waugh and Jamie Barker.

This is the second time this school year that students and staff have been asked to avoid the area of Norlin Library.

The university was placed on a shelter-in-place order Aug. 25 after reports of shots being fired near the library. That call turned out to be a hoax, according to university police.

Friday’s threat came two days after a student shot himself and two other students at Evergreen High School in neighboring Jefferson County, and one day after nearby Fairview High School and Summit Middle School were placed on lockdown after a runner wearing a weighted vest and holding a cell phone was mistaken for a man holding a gun.