Reports of gunshots were heard near Brownsville TMs Veterans Memorial High School on Thursday evening.
One viewer on Facebook, who was picking up her daughter from softball practice, said teachers were yelling at students to run inside or to go into their cars.
Interim Police Chief Orlando Rodriguez told Action 4 News that three adult males were arrested on Vasquez Road, a half-mile near the high school, for shooting guns and rifles.
They are all being charged with discharging a firearm in city limits.
The men were not aiming at anyone when firing the weapons and no one was harmed.