TONOPAH, Ariz. -- A missing Arizona woman was found slain in a shallow grave last week, and authorities have arrested a man with whom she went on an online date, reports CBS affiliate KPHO.

25-year-old Angela Russo had been missing since April 19, after reportedly meeting her suspected killer for a date in West Phoenix. Lashawn Johnson, who was already in jail on unrelated charges, was charged with her murder on Sunday, the station reports.

Russo's body was found buried in the desert in Tonopah, about 50 miles west of Phoenix. Her car was reportedly found burned nearby.

Get Breaking News Delivered to Your Inbox

Russo's mother Diana Schalow told the station her daughter met Johnson on an online dating site. She said she was devastated to learn of her daughter's death and was hoping the search would "end differently."

"It does actually give us a slight bit of closure," Schalow said. "You go to sleep with different pain but at least, we've gone searching for her so many times."

Russo's cause of death hasn't yet been released.