AMHERST (CBS) – A shelter in place order has been lifted at UMass Amherst after a student was assaulted by a person with a gun.

An alert sent out to students Thursday afternoon said there was a “hostile armed person reported in Pierpont Hall.” UMass Police officers secured a perimeter and interviewed witnesses.

About an hour later, the university told students to resume normal activities.

ALERT: Shelter in place order HAS BEEN LIFTED. Please resume normal activities. Additional information will be provided by UMass email. — UMass Amherst (@UMassAmherst) February 19, 2016

UMass Police say a student was assaulted by two suspects in Pierpont Hall, a residence hall for first year students, at about 5:15 p.m. The two suspects fled campus and police are currently “vigorously pursuing leads.”

Police say a handgun was shown during the incident but was not fired. The suspects are not believed to be UMass students.

The victim, who is a student, suffered a laceration to the head and is being treated at a local hospital. The assault is not believed to be random.

“Our officers responded promptly and our community responded well to the emergency communications that we shared in a timely manner throughout the incident,” said UMass Police Chief Tyrone Parham. “I want to thank everyone involved for their assistance and cooperation.”

ALERT: Hostile armed person reported in Pierpont Hall. UMPD on scene and perimeter secured. Please shelter in place. — UMass Amherst (@UMassAmherst) February 18, 2016

ALERT: Suspect is a white male wearing dark colored shirt and gold chain. Reports of 2nd involved party, white male wearing gray sweatshirt. — UMass Amherst (@UMassAmherst) February 18, 2016

UMass Amherst’s 1,400 acre campus is about 90 miles west of Boston. Currently, 22,000 undergraduate students attend the school.