YOUNGSTOWN, Ohio (AP) — A Pennsylvania man was sentenced to 18 months in federal prison for sending an online message to a suburban Cleveland high school student in 2018 about a shooting he warned would occur the next day.

That warning led hundreds of students to miss classes, authorities said.

Russell Miley-Cruz, 22, of Scranton, was sentenced Tuesday in Youngstown and will receive credit for the 11 months he has been confined since his arrest, his attorney said Wednesday. Miley-Cruz pleaded guilty in September to transmission of a threat in interstate commerce and obstruction of justice.

Miley-Cruz contacted a Parma High School student on Snapchat in April 2018 warning of an impending school shooting, prosecutors said. The obstruction charge stems from Miley-Cruz providing investigators with a false phone number and denying that his Snapchat user name was “djravetastic.”

The student who received the message shared it with friends who then passed it on to others. Around 1,200 students stayed home the following day with only 340 attending classes, prosecutors said.

Defense attorney Dave Betras said Miley-Cruz has struggled with mental illness his entire life and called his client “extremely naive.”

“He didn’t appreciate how wrong his actions were at the time,” Betras said.