An elderly man who had been missing for at least three days in the New South Wales Hawkesbury region has been found safe and well, with the help of his dog.

Emergency services launched a full aerial and ground search for the 84-year-old after his family raised the alarm.

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Police Inspector Peter Jenkins said the man’s English Staffordshire terrier Kiaria appeared from the bushland and led emergency crews to the man.

“His dog started barking, ran to one of the sons and ran into the bush,” Inspector Jenkins said.

“PolAir got a coordinate for that and started circling to find them.”

Inspector Jenkins said early investigations indicated that the man may have fallen while walking the dog.

“Rescue crews got to the gentleman, found him to be conscious, breathing, he had a facial injury which was consistent with him falling over,” Inspector Jenkins said.

“He was severely dehydrated, hallucinating and disorientated.”

The man was stabilised by medics on the scene before being winched aboard the air ambulance and flown to Westmead Hospital in a stable condition.