The incident was not picked up on her security cameras.
Donna Robert made the shocking discovery Monday morning on her Stevenson Ranch property.
"I’m like, 'That looks like a tombstone,'" the stunned homeowner told CBS Los Angeles. "The stone was shiny and I could see the word Timothy, and I didn’t look any more."
When she ran back inside, she alerted her family and checked the security cameras. Nothing showed up in the footage and she says the stone was never there before.
She called 911 and police arrived to check out the scene and called local cemeteries to see if they were missing a stone plot. The Santa Clarita Valley Sheriff's Department told InsideEdition.com that none claim to have anything missing or vandalized tombstones.
The Sheriff’s Department released the images of the tombstone on Twitter Tuesday evening.
FOUND TOMBSTONE in Stevenson Ranch-It was in homeowner's front lawn. This is actual pic. For privacy, some info has been left out. pic.twitter.com/CAPe9dhTF5— SCV Sheriff (@SCVSHERIFF) March 14, 2017
"We are befuddled as to where it came from and as of now it is recorded as 'found property,'" Sgt. Dan Peacock of the Santa Clarita Valley Sheriff's Department told InsideEdition.com.
Commenting on the mystery surrounding the case, Sgt. Peacock said, "In my 28 years [in law enforcement] nothing is strange anymore."
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The Sheriff’s Department was actively updating its Twitter account with information on the mysterious tombstone.
Just when you've heard it all... then a Patrol deputy gets a call where an informant reports finding a tombstone in their front yard, ?— SCV Sheriff (@SCVSHERIFF) March 13, 2017
.@NewsSourceLA We are unable to release the photo, as it has a name on it. A detective is trying to find out where it came from.— SCV Sheriff (@SCVSHERIFF) March 13, 2017
Update on the tombstone found in someone's front yard. Our local cemetery did not recognize it. The investigation continues.— SCV Sheriff (@SCVSHERIFF) March 13, 2017
Officials are still working to find who would place the tombstone on Robert’s property.
She told CBS that she hopes it finds its proper resting place.