With new information, the FBI and Savannah-Chatham police are asking the public to keep helping them in their search for the armed gunman who robbed a Wells Fargo bank Friday afternoon. Investigators believe that in addition to the ball cap and surgical mask that concealed his face, the suspect wore a long wig as part of his disguise when he walked into the bank on the 5700 block of Waters Avenue, produced a handgun and demanded money, said police spokeswoman Eunicia Baker.