Two childhood friends from Long Island were murdered Sunday in an apparent double murder-suicide in Arizona. Police say Carol Kestenbaum, of Bellmore, was a sophomore at Arizona State University. Nicole Schiffman, of Merrick, went to visit Kestenbaum to celebrate her 20th birthday. Tempe police say the pair was coming home from a night out when 22-year-old Joshua Mendel shot them both in the parking lot of Kestenbaum's apartment. Police say Mendel then turned the gun on himself. Officials say they believe Mendel was upset that Kestenbaum told his girlfriend she didn't like him. Friends and family say Kestenbaum and Schiffman had remained close friends since graduating from Kennedy High School in 2005. Police say they located Mendel's body with the weapon at his side. They say a second weapon and additional ammunition were in his pockets. Police have contacted Mendel's girlfriend, who they say was not involved in the shooting.