HOUSTON (CW39) — Parents were terrified on Tuesday, after an alert went out of an active shooter, at Heights High School. However, the incident turned out to be a false alarm.

No injuries were reported and students were released to their parents at a re-unification center.

The Houston Independent School District said that the Houston Police Department and HISD police said they and the FBI would continue to investigate the threat, “though no evidence was found to substantiate the threat,” a district statement said. 

After the incident, and all students were determined to be safe, Houston Mayor Sylvester Turner released a statement about the response of local law enforcement.

“I want to thank Houston Police, Houston Fire, the Harris County Precinct One Constable’s Office, and Houston ISD for their prompt response at Heights High School,” Turner said.

“While the reports of an active shooter turned out to be false, we are reminded that student safety and school security are paramount on the minds of students, parents and employees of all school districts. Today’s response to the emergency calls reinforces how seriously our first responders take these incidents, and illustrates the constant training they undergo to take such quick and responsive action.”

The incident was part of a number of other hoax calls made to several schools in central Texas and California.