Wisconsin police say a person toting a rifle opened fire outside a high school prom, leaving three people injured.

Antigo Police Chief Eric Roller says in a statement that the shooter "showed up" Saturday night at Antigo High School and started firing at two people outside the building.

Roller says officers in a nearby parking lot heard gunshots, and an officer fired upon the shooter, "stopping the threat." Roller says everyone at the prom was eventually "escorted from the school and are safe."

It was not immediately known if the unidentified suspect was among the injured at the hospital, or if they were a student. Roller says the shooter was in custody.

The condition of those injured wasn't immediately known, but Roller says all three were taken to the hospital.