The FBI has determined threats made to four Northern Nevada high schools on Wednesday morning were a hoax. 

We are learning more about the bomb threats made to the school districts.

The Storey County Sheriff's Office (SCSO) said at 6:06 a.m. Wednesday morning, officials from Virginia City High School and the Storey County School District Superintendent's office reached out about an email threat.

The threat claimed there was a pipe bomb somewhere on the VCHS campus, and it would go off around noon.

Officers from SCSO, Sparks Police, Washoe County Sheriff's Office, Nevada Capitol Police, and Airport Authority Police responded to the scene.

Bomb detection K9s did not find any evidence of explosives.

Out of an abundance of caution, SCSD closed Virginia City High School for the day and put the rest of its schools on a 2-hour delay.

In an email sent to parents, Douglas County School District Superintendent Frankie Alvarado said the district immediately evacuated its schools upon learning of the threat.

Wednesday was a professional development day, so very few students were at school. Staff were sent home.

Officials from the Douglas County Sheriff's Office and Tahoe Douglas Fire Protection District searched Douglas High School and found no explosives.

Once the threats were determined to be a hoax, local authorities agreed that no other Douglas County schools needed to be checked.

In the capital city, the Carson City Sheriff's Office briefly put Carson High School on hold, but reopened with extra security. Officers did not find any evidence.

Churchill County School District received a similar threat. On Facebook, it said it has increased security measures at Churchill County High School.

The investigation into the origin of the threats is ongoing.

In a statement, the Nevada Threat Analysis Center said it knows about the threats and is working with local law enforcement to figure out where the threats originated from.

The agency said it is not aware of any physical bombs or suspicious activity.

"The Nevada Threat Analysis Center is conducting analysis related to the threats and sharing information with appropriate law enforcement partners conducting the investigation into these incidents," said the NTAC in a statement.