A $1,000 reward is being offered for information leading to an arrest and conviction of the person or persons who left a threatening message on a stall in a boys bathroom at Tippecanoe Middle School on Tuesday.

The discovery of the threat prompted district officials to evacuate the school so K-9 units from Wright-Patterson Air Force Base could search the building. Nothing dangerous or out of the ordinary was found, according to Tipp City Schools Superintendent John P. Kronour.

Tuesday’s threat follows three consecutive threats last week — on Wednesday, Thursday and Friday. Until Tuesday, all of those threats were found at the district’s high school. Tuesday’s was the first at the middle school.

“It’s getting old,” Kronour said.

Tipp City police Sgt. Chris Graham said a phone message went to parents offering a reward to anyone with information that leads to one or more arrests stemming from the threats.

An initial reward of $500 was increased to $1,000 late Tuesday night, according to police and school officials. Earlier Tuesday, Graham had said the reward could increase because several people expressed interest in adding to it.

The person responsible for making the threats could face felony charges.

Graham said that between the costs associated with overtime for officers and investigators, response-time costs and bomb-sniffing dogs, thousands of dollars have been spent responding to the threats.

Kronour has said district officials are working with police to heighten security at the school.

He also said officials are working to keep parents informed through recorded phone messages that parents receive if they sign up for them. Some parents are becoming aware of the incidents early as students are texting them from school.

“We’re doing everything we can to make sure students are safe,” Kronour said.

A public meeting will be held Wednesday at 7:30 p.m. at L.T. Ball Intermediate School. Kronour, Graham and FBI Special Agent Timothy Ferguson will address any questions regarding the threats or safety measures at the schools.