Early Thursday morning, rangers at Rancho San Rafael Regional Park near the UNR campus found several acid bombs by one of the picnic pavilions. Acid bombs are usually made with plastic containers, such as plastic bottles, and contain volatile household chemicals like drain and toilet bowl cleaners, along with other ingredients. They have several names including: work bombs, chemical bombs, Drano bombs, and bottle bombs. Bob Harmon with the Washoe County Sheriff's Office advises anyone who sees a suspicious bottle, which would have fluids in it and aluminum foil, not to handle the situation themselves. "With these acid bombs, if they do explode, they can spray some incredibly hot, boiling liquid which, of course, can be critical to whoever's nearby, or the plastic when it explodes can become sharp." The rangers discovered the bottles at 6:30 and called the sheriff's office. The park re-opened by 8 am.