Dallas County High School was evacuated Monday morning after a bomb threat was made to the school.

Captain Mike Granthum with the Dallas County Sheriff’s Department said a phone call was made to the school sometime between 10:45 a.m. and 11:15 a.m.

Granthum said students and teachers were evacuated while investigators searched the school looking for anything suspicious.

“We’re treating it serious until we find out anything different, but we’re going classroom to classroom and searching and seeing if we see anything,” he said. “We’re trying to find out exactly where [the call] came from. We’re going to trace the line and see if we can find out where that call came from.”

Granthum said if anything suspicious was found, the state’s bomb squad would be called out.

As of noon Monday, Granthum said nothing suspicious had been found. School officials confirmed shortly after noon that students and teachers were back in class.

Even though there were no signs of the situation being a serious threat, Granthum said the department takes all threatening phone calls to schools serious.

“We’ve never had one as of yet to be for real, but we still always take them like they’re serious because we never know,” he said. “It could possibly be, but we don’t have any reason to believe it is [serious]. We don’t want to take any half steps. We want to make sure it’s not.”

Granthum said it is not uncommon for schools to get these kinds of calls near the end of the school year. A phone call was made to Keith Middle High School just last week threatening a shooting at the school.

“A lot of times, especially this time of year towards the end [of the school year], these calls do tend to be more frequent than most times, especially during exams,” Granthum said. “I’m not saying that’s the instance here, but we always treat every one of them like there is a bomb in the school. We want everyone to be safe.”

Granthum said if the call can be traced back to someone they could be facing a felony charge of making a terrorist threat.

“This is something serious,” Granthum said. “Used to it was just harassment, but it’s so frequent now.”