A Lewis and Clark High School student suspected of threatening to shoot his classmates is also accused of sending sexually explicit messages to a 15-year-old girl.

Ryan B. K. Lee, who turned 18 two months prior to posting shooting threats online, is being charged as an adult. In addition to facing felony harassment charges, he’s also charged with communicating with a minor for immoral purposes, which if convicted, would require him to register as a sex offender.

In charging documents filed Friday, Spokane police Detective Jeffrey Barrington said a 15-year-old female student reported receiving violent sexually explicit threats and pornography from May 26 to 29 from an Instagram account by the name of steven_smith_4.

The messages also said he was “going to shoot up LC!!!!”

Court records say that another female student, who is at least 18 years old, sent the account a message asking him to stop, to which he replied, “Its going to take place whether you like it or not.”

Both students reportedly took the threats seriously and feared they could be shot, court records say. The same Instagram account had a message in its biography section saying it had a “special date planned for LCHS before the end of school.”

On May 30, detectives served a search warrant on Facebook to find an IP address tied to the account, which led them to Lee, who was apparently accessing the account on his iPhone and Microsoft tablet, according to court records. That same day, more than half of Lewis and Clark’s student body did not go to school out of fear.

Kevin Morrison, spokesman for Spokane Public Schools, said once school officials were made aware of the student’s identity, the discipline process began and he was subsequently expelled. Speaking generally, he said the only contact they would have further with the family would be to notify them of their son’s discipline status.

On the afternoon of May 30, detectives stopped Lee in a BMW near North River Drive and Washington Street, where he was driving with his mother and sister, court records say.

Court records say Lee initially denied having the Instagram account and denied sending any messages to anyone referencing a school shooting. During a second interview, he admitted to creating the account and sending the messages and images to the 15-year-old girl, according to records.

He also denied he was “going to actually go and shoot anyone or go to Lewis and Clark to commit a school shooting,” court records say. Lee also denied owning or having access to firearms.

Detectives seized Lee’s iPhone and tablet and were granted a search warrant on May 30 to explore their contents.

Lee was admitted to Providence Sacred Heart Medical Center, where he remains under a voluntary mental health evaluation.

According to a recent search of Spokane County jail records, Lee has not been arrested.