JULIAN, Calif. (AP) — Authorities in San Diego County are searching for a missing woman with Alzheimer’s disease who is the mother-in-law of Megadeth frontman Dave Mustaine.

U-T San Diego reports (http://bit.ly/1qbygSE ) 75-year-old Sally Estabrook was last seen Saturday at an RV park and campground in Julian.

Search-and-rescue teams from four counties and the U.S. Border Patrol fanned out Tuesday in an area near state Route 79 to look for her.

Sheriff’s officials are asking nearby business owners to look through surveillance footage.

Estabrook is the mother of Mustaine’s wife, Pam.

In a post on his Twitter account Monday, the metal singer and guitarist asked people to “please send good thoughts to Pam, and prayers from those of you who pray.”

Megadeth’s latest album, “Super Collider,” came out last year.

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Information from: U-T San Diego, http://www.utsandiego.com

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