A student prank involving an active shooter hoax led to a modified lockdown and significant law enforcement response Thurday at West Valley High School.

A student who was at home contacted 911 and the Yakima County Sheriff’s Office around 12:35 p.m., saying he received a group text message from other students about an active shooter incident happening at the high school, according to a news release from the Yakima County Sheriff’s Office.

The student was concerned and called law enforcement. Officials from the Yakima County Sheriff’s Office, the Yakima Police Department and the U.S. Bureau of Alcohol, Tobacco, Firearms and Explosives responded, along with fire and ambulance services.

The high school and nearby freshman campus were placed on a lockdown until law enforcement determined it was a hoax, the sheriff’s office said. Shortly before 1 p.m. officials verified that there was no active shooter, Superintendent Michael Brophy said.

Brophy said area schools were placed in secure and teach, a form of lockdown that allows teaching to continue, but limits movement on campus.

District communications director Anjerie Nemrow said this included the high school and freshman campus. Cottonwood Elementary School was in a “test only” drill, she said.

“Officers did a sweep of the school and there was no active shooter. We are back to regular teaching,” Nemrow said midday Thursday.

She said the secure and teach was lifted at the high school at 1:18 p.m., and at the freshman campus at about 1:30 p.m.

Sheriff’s office Lt. Aaron Wuitschick said the school district, the sheriff’s office and other agencies had conducted training exercises for dealing with an active shooter at the school.

“It definitely paid off,” Wuitschick said. “It was nice to have that kind of cooperation beforehand.”

Deputies investigated the incident and found a group of students was pranking the student at home “and did not think of the consequences of the hoax,” the sheriff’s office release said.

An investigation is continuing. Charges may be filed through the Yakima County Prosecutor’s Office, the release said.

The sheriff’s office encouraged all parents to discuss proper use of social media with their children.