Two people were arrested after an explosion at a Riverside apartment led to the discovery of a butane honey oil lab, police said Thursday. The 6 a.m. Monday blast in the the 600 block of Central Avenue displaced neighbors as police and firefighters responded to the scene, the Riverside Police Department said in a news release. Fire investigators determined the cause of the fire was a butane honey oil lab that was set up inside one of the apartments, where they spotted empty butane canisters, hash oil extract and marijuana plants, according to police. Butane is a flammable and odorless...