DALLAS (CBSDFW.COM) – Family members are pleading for help from the public finding a Dallas man who suffers from dementia. It’s been nearly a week since Roy Lee Cook Sr. went missing.

The 70-year-old was captured on security camera leaving his niece’s home, in the 800 block of Lawton Drive in the Pleasant Grove area, just after midnight on Thursday morning. The camera shows Mr. Cook walking outside without his glasses or cane. The elderly man wasn’t fully dressed; wearing only pajamas and no shoes.

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(credit: CBSDFW.COM)

Today the family, along with the Justice Seekers, held a press conference to ask North Texans to be on the lookout for Mr. Cook, who they say suffers from Alzheimer’s, dementia and has other health issues.

Mr. Cook’s niece, Veronica Cook Fields, said, “Right now we know, if he’s still out there, he needs help. He needs help. As they said he’s very fragile. We see on the [security] video that yeah he was walking fast, but right about now we don’t know anything.”

Family and friends say they have been looking for Mr. Cook everyday.

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Mr. Cook’s son, Roy Lee Cook Jr., told CBS 11 News reporter Steve Pickett that his father has wandered away before, but usually makes his way back home or is found before getting too far.

“We love our family member and we are gonna do everything we can to bring him back home, so please help us,” implored Cook Jr. “He’s sick and we’re just worried about him. We just want some closure. Dead or alive I just want him found.”

Dallas police had issued a Critical Missing Alert for Mr. Cook but quickly changed that to a Silver Alert.

Roy Lee Cook Sr. is a black man who stands 5’11” and weighs about 125 pounds. He has gray and black hair and brown eyes. Mr. Cook was last seen wearing a white t-shirt, and either red and white or red, white, and black pajama bottoms.

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Anyone with information about Mr. Cook’s whereabouts is asked to call 911 or Dallas police at 214-671-4268.