A call of shots fired that sent scores of heavily armed officers to a Northwestern University graduate dorm Wednesday afternoon was apparently a case of “Swatting,” a false emergency designed to draw a large police response.

Alerts were issued and teams of police were dispatched, but officers found the woman – a Northwestern student – unharmed with “No evidence of a victim, scene or gunman,” said Evanston police Cmdr. Ryan Glew, a spokesman for the department.

The alert initially went out to students and staff shortly before 2:30 p.m., warning them to stay away from the area of Engelhart Hall, which has apartments for Northwestern graduate students and their families.

Even after police found no evidence of a victim or weapon, officers continued their search and Northwestern tweeted that people inside Engelhart “Should remain behind locked doors.”

Swatting is the practice of placing hoax emergency calls with the aim of drawing a large response from law enforcement.

As Taft had pointed out, the Northwestern alert went out not long after students participated in Wednesday’s National School Walkout.

Hundreds of Northwestern University students gatd in Deering Meadow on campus in support of a national effort for tighter regulations on gun sales after a high school massacre in Florida.

Police: ‘Swatting’ prank call led to Wichita police shooting unarmed man .