A gunman wearing a medical mask robbed American Savings Bank in Liliha yesterday of an undisclosed amount of cash.

The robbery at 1425 Liliha St. was reported at 5:15 p.m.

Police Sgt. Kim Buffet, Honolulu CrimeStoppers coordinator, said the suspect approached the teller, displayed a gun and demanded money. He was last seen running on Liliha Street toward Vineyard Boulevard. A second man, also wearing a medical mask, was seen outside the bank with the suspect before the robbery.

The suspect is about 5-feet-6-inches tall and 135 pounds. He was wearing a gray T-shirt, long black pants, white athletic shoes, a black do-rag on his head, prescription glasses and carrying a yellow backpack.

Anyone with information on the suspect can call Honolulu CrimeStoppers at 955-8300 or *CRIME on a cellular phone.

The bank robbery was O'ahu's 11th this year and is the only case in which a suspect has not been charged.