UCSB student William Calabrese passed away Sunday from injuries he suffered during a fireworks explosion in Riverside County on Friday. Calabrese, 20 years old and a Pacific Beach native, was helping prepare a fireworks demonstration for a Lake Elsinore Storm minor league baseball game when the explosion occurred. Calabrese suffered burns to 90 percent of his body. Two other people were injured, and a truck was destroyed. The cause of the explosion is under investigation.