Investigators once thought the "Geezer Bandit" was at least 60 years old. Now they're not so sure _ unless he discovered the Fountain of Youth after his most recent holdup, when he was seen sprinting across a parking lot.
Witnesses also said he might have been wearing a mask.
The new evidence suggests the elderly-looking thief may not be in the sunset of his life after all but rather a younger person trying to throw authorities off his trail.
The robber has struck 16 banks, stretching from San Luis Obispo to San Diego, during the past two years. He also has become somewhat of a celebrity in Southern California, with his face printed on T-shirts, trick-or-treaters imitating him and more than 12,000 people liking him on a Facebook page.
But the bandit may be slipping. On Dec. 2, after pulling out a handgun and threatening to shoot a teller, he became disoriented when a security dye-pack exploded as he was leaving the bank, authorities said.
Video surveillance shows he tried to grab the money and his belongings then ran away and wasn't caught.
A day planner used to conceal the gun was recovered and is being examined by investigators, FBI spokeswoman Laura Eimiller said.
After seeing the video of the spry robber and hearing witness accounts that he might have worn a mask and gloves, authorities are rethinking their theory about him.
"If somebody told me this was truly an elderly person, it's possible," Eimiller said. "We're working under the theory that it's very possible he's wearing a mask."
Investigators have sought assistance from mask manufacturers in hopes of catching the robber, but they wouldn't say if they have found any leads. One mask bearing deep wrinkles and blemished skin known as "The Elder" has a striking similarity to surveillance photos released of the "Geezer Bandit."
The last five robberies have occurred on Fridays.
On Dec. 9, a man who appeared to be wearing a mask walked into a Camarillo bank. Employees said the man appeared to be wearing a mask, and when he was approached, he said his wallet was in his car and left, Eimiller said.
Authorities believe it might have been the "Geezer Bandit," or perhaps a copycat, casing the bank, she said.
The FBI and various banks are offering a $20,000 reward for information leading to his arrest and conviction.