HOUSTON (Nexstar) — The FBI Houston Field Office said Wednesday it is working with the Houston Police Department to investigate a hoax threat to a high school Tuesday, but cannot confirm if it is connected to several other similar threats to school districts across Texas, which have all happened within the last 24 hours.

On Tuesday, several campuses in Texas received false reports of threats to school districts, including three in Houston and one in Waco, which resulted in heavy law enforcement response and floods of anxious-ridden parents.

Anthony Messa was one of many parents who flooded outside Heights High School in Houston after hearing about a possible active shooter situation at his child’s school. He told Nexstar affiliate KIAH he was relived it was a false alarm but not surprised.

“I think everybody’s kind of numb to the situation. It’s just happens every week, one place or another,” Messa said.

Another Heights High parent, Lynda Guerrero, said even though she was initially terrified over what ended up being a hoax threat, she was pleased with the police response.

“Any student could have been affected. It just gives me chills. So yeah, I was not doing good,” she said. “Whether it’s false or not, it’s like a peace of mind. It’s comforting to know that our kids are safe.”

The false threats of shooter-type situations were not isolated to Tuesday. In Odessa, a fifth grader was arrested Wednesday after he told classmates he was going to shoot up the school, shaping his hand to form a gun. Credible threats were made to Amarillo ISD, Harlingen ISD and at least two San Angelo ISD school campuses this week.

Credible or not, any news of school shooting threats are triggering to parents like Brett Cross, who lost his son, Uziyah Garcia, in the May 24 Uvalde school shooting massacre, which killed 19 students and two teachers.

“As soon as you hear oh, this school is on lockdown, you’re thinking, ‘not another child, not another parent that we have to welcome into this club that we don’t want to be in.’ But it is very frustrating,” he said.

Cross worries if hoax threats continue, schools will become complacent if it starts to feel like ‘the boy who cried wolf,’ which a Texas House committee referenced in its investigative report about what went wrong in Uvalde.

“I do fear that the schools will become complacent, because we became complacent,” he said. “Hell, at first, when they said [Robb Elementary] was going on lockdown for me, it happens all the time. So with these threats being made — and this continued, continuously happening — people, the schools will get careless with it. And then you have another May 24th.”

The Texas Education Agency does track how many threats are reported to Texas’ 1,026 school districts on a yearly basis and what happens with those threats.

According to data TEA collected from school districts and given to KXAN, there were nearly 67,500 threats made during the last school year. Out of those, about 17% posed a threat and individuals were referred to officials for intervention. Only about 3% actually posed an imminent threat. The vast majority of reports — 69% — posed no real threat to school district.