FORT LAUDERDALE, Fla. (AP) — A California man who is on the autism spectrum was sentenced Monday to more than five years in prison for cyberstalking families of Parkland, Florida, school shooting victims.

U.S. District Judge Rodolfo Ruiz imposed the sentence on 22-year-old Brandon Fleury of Santa Ana, California, rejecting a request by prosecutors for the maximum 20-year sentence.

Fleury was convicted by a jury in October of three counts of cyberstalking and one count of transmitting a kidnapping threat.

Trial evidence showed that between December 2018 and January 2019, Fleury used several Instagram accounts to threaten and harass families of victims of the Valentine's Day 2018 shooting at Marjory Stoneman Douglas High School, which left 17 dead and 17 wounded.

In some messages, he claimed kinship with and even impersonated shooting defendant Nikolas Cruz. In others, he invoked the names of infamous serial killers such as Ted Bundy.

“I killed your loved ones hahaha," one message said. “Did you like my Valentines gift? I killed your friends,” said another.

One of his user names was “nikolas.cruz.killed.your.sister," court records show. One message from that account said this:

“Hahaha she had her whole life ahead of her and I STOLE IT FROM HER," according to court documents.

“The victims lived in constant fear that the individual bombarding them" with the messages would follow in Cruz’s footsteps, Assistant U.S. Attorney Ajay Alexander said in court papers. "The victims deserve justice. They deserve to live in peace and with the belief that they are safe and secure."

On Fleury's electronic devices, authorities also found thousands of saved images of Bundy, images of the targeted victims and screenshots of the messages that he had sent the victims.

“The danger that Fleury poses is clear and if given the opportunity, there is a real danger that he will attempt to follow in the footsteps of the very mass murderers and serial killers that he idolizes,” Alexander said.

There was ample testimony at Fleury's trial that he is autistic, although several mental health experts said he did understand right from wrong.

Yet his attorney, Sabrina Puglisi, said she had hoped the judge would give greater weight to his mental issues in imposing a sentence.

“I think that it’s a high sentence given Brandon’s background and other similarly situated cases, but I believe that the judge felt the need to have the sentence send a message to others that are out there on the internet doing this bad behavior,” Puglisi said.

Meanwhile, Cruz, 21, faces the death penalty if convicted in the Parkland shooting. His lawyers have said he would plead guilty in exchange for a life prison sentence, but prosecutors have rejected the offer.

Cruz's trial is expected to begin sometime later this year.