The Texas Silver Alert Network issued an alert in the search for 67-year-old Jessie Sanchez early Thursday.
Dallas police identified him as a critically missing person late Wednesday.
He was last seen Wednesday around 2 p.m. walking on the 8800 block of Woodcastle Drive in the Pleasant Grove neighborhood wearing a Marine cap, yellow, blue and white sweater, black jeans and black shoes, according to police.
Officials believe he may be confused and in need of help.
He is about 5 feet 7 inches tall, weighs around 180 pounds and has brown eyes and a bald head.
Anyone with any information should call 911 or police at 214-671-4268.
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