A 22-year-old California man has been convicted of threatening and cyberstalking the friends and families of those killed in the 2018 mass shooting at a Parkland, Florida, high school .

A federal jury in Florida on Tuesday found Brandon Michael Fleury guilty of three counts of cyberstalking and one count of transmitting a kidnapping threat. He faces up to 20 years in prison.

Prosecutors said Fleury used online aliases including the name of the confessed Parkland shooter Nikolas Cruz and notorious serial killer Ted Bundy while targeting and harassing his victims via 13 different Instagram accounts over the course of three weeks.