SAN DIEGO -- A young masked man robbed a North City bank Monday, authorities reported.

The thief, who appeared to be in his late teens or early 20s, approached a teller at the JPMorgan Chase Bank branch office in the 2700 block of Via de la Valle and demanded cash about 10 a.m., according to the FBI.

The bandit, dubbed the "Double Layer Bandit" by authorities, claimed to be carrying a gun, though none was seen. He fled with an undisclosed amount of money to the east in a small sedan, possibly a Toyota Corolla.

Witnesses described the robber as a thin, pale, dark-haired, roughly 5-foot-9-inch youth dressed in shorts, white sneakers and a gray hooded sweat shirt with a dark-colored T-shirt worn over it. The bottom half of the thief's face was covered with black cloth, the FBI reported.