Lyons Township High School in west suburban Western Springs was evacuated Saturday afternoon as police searched the building for a person with a gun.

About 12:50 p.m., officers responded to Lyons Township High School’s South Campus, 4900 W. Willow Springs Road, to investigate a report that someone entered the school with a gun concealed in his pants, according to Western Springs police. A person told officers they saw the suspicious man headed toward the school’s pool facility.

The man, described as white, in his early 40s, of average building and wearing a ball cap, dark sweater and tan pants, was said to have had a noticeable bulge in his right pants pocket, police said.

Officers worked with school officials to clear the building and search the school, police said. The school was declared safe at 3:55 p.m. and nothing suspicious was found.