Megadeth frontman Dave Mustaine has pleaded for help in finding his missing mother-in-law.

Sally Estabrook, 75, is suffering from Alzheimer’s disease and hasn’t been seen since Saturday afternoon. Police say the last sighting was at a campsite near her San Diego home. Her husband raised the alarm.

Mustaine tells KFMB: “My wife is very, very upset. With Sally having Alzheimer’s, it complicates it so much.”

His son Justis says: “We miss her. We want her to come back. We want to find her. She’s been out there two nights already, no food, no water, nowhere to sleep. We just hope she’s all right.”

Sally Estabrook is described as 5ft 4in tall with shoulder-length blonde hair, wearing a blueish top and white trousers. It’s thought she may answer to her name. Anyone with information is asked to contact San Diego Sheriff’s Department on (858) 565 5200.

Mustaine last night tweeted: “Please send good thoughts, and prayers from those of you who pray, as we search.”