RALEIGH — Police are making a new appeal to the public for help in finding the seemingly invisible man who robbed a First Citizens bank in December and was clearly captured by a security camera but who has been unseen and unheard of since.

Detectives have been unable to come up with leads so far, but they feel someone must know the man seen in the photo that is unusually clear and sharp for a security-camera image, police said Sunday.

The black man is of average build and was wearing a white shirt, dark jacket, blue pants and brown hat, police said.

They think he walked north from the bank at 239 Fayetteville St. after the Dec. 3 robbery.

The man handed a teller a note demanding money, got it and walked out of the bank, police said.

Police asked that anyone with information that might help them call Raleigh CrimeStoppers at 919-834-HELP (4357) or to go to the CrimeStoppers website to find out how to give police a tip online or by text message.

CrimeStoppers pays cash rewards for anonymous tips that help solve cases.