WATERLOO - A Windsor Heights teen has been convicted of sending threatening text messages to his former girlfriend while she was at the University of Northern Iowa in March.

The messages - which talked about purchasing a gun, using drugs and driving to Cedar Falls -- prompted UNI police to lock down the campus.

Magistrate Joseph Sevcik found Todd Michael Younk, 19, guilty of third-degree harassment, a misdemeanor, in a written ruling signed Monday.

"The text messages used various obscenities and stated that the sender now hated her and that he did not want to her to go to prom with him any more," Sevcik wrote in the ruling.

Younk waived his right to a jury and allowed the magistrate decide his fate during Dec. 1 bench trial.

Defense attorney Benjamin Bergmann had argued there was no concrete evidence that Younk sent the messages. And if he had, the messages didn't put his former girlfriend in fear of her own safety, he argued.

Two of Younk's friends testified for the defense and said they were with him at the time the messages were sent. But they said they didn't see him using his phone.

They said Younk had been playing video games and Frisbee golf at the time.

Prosecutor Linda Fangman noted the ex-girlfriend and another acquaintance at UNI had briefly spoke to Younk on the phone about the messages, and he said he was sorry.

Windsor Heights police found Younk with the phone when he arrived at his mother's house in Windsor Heights. He was unarmed without any plans to come to UNI.

"The court has no difficulty in finding that the state has proven beyond a reasonable doubt that the defendant was the individual who was texting the messages on his cell phone," Sevcik wrote.

He also noted that witnesses reported seeing the ex-girlfriend crying during the time when the messages were sent.

At trial, she testified she feared Younk would do something to kill or injure himself.

Sevcik said it didn't matter if she was concerned for her own safety or for his.

"Rather, the state must prove that the defendant communicated in a manner likely to cause another person to be annoyed, alarmed or intimidated," he wrote.

Sentencing has been scheduled for Dec. 23.

Younk and the woman had dated during high school but had broken up. At the time of the March incident, she was a freshman at UNI, and he was a senior in high school.

Contact Jeff Reinitz at (319) 291-1578 or jeff.reinitz@wcfcourier.com