Schools nationwide are on heightened alert in the wake of last week's fatal shootings in Broward County, and in the Tampa area, that means official warnings about social media posts and more calls for police action.
Two Tampa boys, one 15 and one 16, were arrested this week for making unrelated threats to shoot up their campuses - one after he expressed disappointment at a bad grade.
Tampa police found no weapons during an investigation that included visits to the teens' homes and determined that their threats at Middleton and Robinson high schools weren't credible.
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Still, police plan to investigate each tip about possible school violence, no matter how big or small, and an arrest could follow if there is a crime to be charged, Tampa Chief Brian Dugan said.
"Everybody is on heightened alert right now," Dugan said at a news conference Tuesday. "If you say something or post something stupid you might end up going to jail for it."
In Pasco County, school leaders took to social media Tuesday in urging parents and students to think carefully about their use of social media to raise concerns about school threat rumors after Facebook gossip spread fear throughout the district.
"Please do not share rumors on social media," the district advised on its official Twitter page. "Tell a responsible adult or call 911 immediately if you hear or see anything that appears to threaten violence at a school."
Seventeen people were killed and 14 were wounded, authorities said, when a former student expelled from Marjory Stoneman Douglas High School returned to the campus in Parkland on Wednesday and opened fire with a semi-automatic rifle.
Tips about students threatening violence have increased since the shooting, Chief Dugan said at a joint news conference Tuesday with Hillsborough County school superintendent Jeff Eakins. These include remarks made by one student to another and on social media.
The two Tampa teens made their threats in person, police said. They now are charged with making a false report concerning the use of a firearm in a violent manner. Police did not release their names because they are charged as minors.
The first arrest was 2 p.m. Monday at Middleton High, 4801 N 22nd St.
The suspect, 15, had been suspended but returned to campus and was asked to leave, police said. He responded by threatening administrators and promising to return the next day to shoot up the school, police said.
He later said he was just talking with other students at the time about the recent shootings in Parkland.
The second Tampa arrest was made Tuesday at Robinson High, 6311 S Lois Ave., in connection with an exchange during class the day before, police said.
The 16-year-old student told his teacher, "If you do not change my grade I will shoot up the school," police said.
Even without weapons found, their violent bluffs broke the law, Dugan said.
"I was very clear with our detectives yesterday that if probable cause exists go ahead and make the arrests," he said. "And whoever it is can explain it to the judge and the prosecutor and go from there."
Even a social media photo of a student with a gun without an attached threat may be enough to warrant a police visit, Dugan said. Some posts may be attempts at a joke, he added, but he sees nothing funny about them.
The Pasco County warnings were issued after Facebook posts describing incidents that never happened, one at Fivay High and the other at Chasco Elementary. The posts arose from threats made elsewhere in the country, but they were enough to cause anguish locally.
Sheriff's deputies investigated and found no credible reason for concern.
Pasco County school superintendent Kurt Browning joined the chorus of officials reminding Florida students that making school threats can result in criminal charges - even if it's only a joke.
That's been state law now for two years.
Contact Paul Guzzo at pguzzo@tampabay.com. Follow @PGuzzoTimes.