TAMPA, FL (WFLA) – A babysitter who was hired through Care.com has been arrested for showing a 10-year-old boy in his care how to set off chemical acid bombs, the Hillsborough County Sheriff’s Office says.

According to detectives, 30-year-old Joshua Stephen Lapin-Bertone of Tampa, was babysitting the boy on Monday night when an off-duty deputy heard a loud explosion in the Logan Gate Subdivision near Monterey Lakeside Park around 11:15 p.m. Detectives say Lapin-Bertone was seen setting off the chemical bombs and showing the boy how to do it. They say he also had the boy participate in throwing them.

Deputies searched his vehicle where they found additional chemicals used to make acid bombs. HCSO responded to the scene where they secured the chemicals. The boy’s mother responded to pick him up.

Lapin-Bertone had been babysitting the boy for a period of 4 years, deputies say.

He’s been charged with four counts of Making/Placing/Discharging a Destructive Device and four counts of Child Abuse Endangerment.