A Santa Ana man is facing charges of using Instagram to send threatening messages to victims of the Parkland, Fla., mass shooting that killed 17 people last year at Marjory Stoneman Douglas High School, according to the O.C. Register.

Brandon Fleury was arrested and charged Friday with cyber-stalking and making threats in interstate communications after federal investigators determined he had created multiple Instagram accounts that were used to taunt those who knew the Parkland victims, according to the L.A. Times.

The alleged threatening social media posts were made between Dec. 22 and Jan. 11, according to the FBI. The messages tagged Instagram accounts used by “relatives and friends of students who were killed in the mass shooting at Marjory Stoneman Douglas High School in Parkland, Florida, on Feb. 14, 2018,” according to NBC.

Starting around midnight on Dec. 22, Fleury began using the account “nikolas.killed.your.sister.” to post statements including “I killed your loved ones hahaha”; “With the power of my AR-15, I erased their existence,” followed by smiling, applause and handgun emojis; and “I took a sh— on your sister’s grave,” followed by a crying-while-laughing emoji, an applause emoji and three poop emojis, according to KTLA.

Authorities identified Fleury as a suspect after pinpointing the IP addresses associated with the Instagram accounts to his family’s home in Santa Ana, according to the San Diego Tribune.