Police have launched an appeal to find Derbyshire trainer Owen Brennan.
Brennan, 77, suffers from memory loss and has been missing from his home on Wheeldon Avenue, Derby, since 4.45pm on Monday.
"Police are searching the area around his home and are now asking residents to check their gardens, garages and any other outbuildings for Mr Brennan," said a statement issued by Derbyshire Police on Tuesday afternoon.
"Mr Brennan is a horse trainer and police have not ruled out the possibility that he may visit racing events. They are asking people involved in horse racing to look out for him.
"Officers are becoming increasingly concerned for his safety as he has memory loss and the weather is cold.
"He is described as white, 5ft 7inches, of slim build, with brown short hair that is going grey.
"He is wearing brown denim trousers with a red cross on the back pocket, a brown cotton type jacket with a wool lining and a fur collar. He may possibly be wearing a cap. He walks with a stoop.
"Anyone who sees him should call Derbyshire police on 101."
Brennan's training career spans over 40 years and his best horses include Vulrory's Clown, Speaker Weatherill and Strath Royal, winner of the Charlie Hall Chase at Wetherby in 1998.
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