Mission Police Chief Cesar Torres was one of many officers busy dealing with multiple threats against schools on Monday.

"We will take any threat serious, so anyone who is found to make any threat to our schools, will be identified, arrested, and prosecuted to the full extent of the law," Torres said.

From Mission, La Villa, Weslaco and all schools in Willacy County, threats emailed to districts forced lockdowns, a large police response and cancelled classes.

All four districts in Willacy County received a message about a bomb threat, forcing them to go into a lockdown.

More than 10 Valley schools reported threats at their campuses, all of them went into a similar response plan which was to search all campuses.

Investigators found the threat to be non-credible, however it still put parents on high alert.

As the last of the Valley schools started their first day, threat after threat was reported across the RGV. 

Willacy County Sheriff Jose Salazar says his office received calls from all four school districts in the county about a bomb threat. 

"We had to scramble units to both locations. We had DPS troopers, local police departments and constable offices," Salazar said.

The threat caused multiple schools across the Valley to activate their emergency response plan.

In Willacy County, that meant kids were evacuated and moved to a safe area. Then law enforcement did a sweep of all campuses.

"All the buildings and areas of the schools, of all schools affected, make sure there wasn't anything suspicious," Salazar said. "We had fire department, EMS on standby. So we have all these individuals together, coming out and making sure the scene is clear."

Law enforcement found all the threats made were not credible.  

Salazar believes the threats originated somewhere other than the valley because districts as far as Laredo received them as well. 

The message sent to multiple districts reads, "I placed multiple explosives in all your schools." School officials say it was sent from a fake email address.

Local law enforcement are leaning on state and federal partners to help find out the people responsible. They hope to prevent this from happening again.

For now, all districts plan to resume school as scheduled on Tuesday.

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