Devion Keith Anderson, 22, was arrested Tuesday after his family called police Monday to alert them he may have killed his 18-year-old girlfriend, the Los Angeles Times reported.
Police dug up the yard and found the victim, whose name has been withheld. The cause of death has not yet been determined.
Anderson faces murder charges. If convicted he could be sentenced to 25 years to life in prison.
He was being held in lieu of $1 million bail.