DEL MAR, Calif. -- Three men in Halloween masks doused tellers with pepper spray Tuesday afternoon while robbing a North City bank, authorities reported.

The thieves entered the U.S. Bank branch office in the 2800 block of Via de la Valle about 4:30 p.m. and ordered employees into a vault, according to San Diego police.

They sprayed workers with a tear gas-like chemical before fleeing with an undisclosed amount of money, possibly in a beige or gold Pontiac Grand Am, SDPD Sgt. Bob Dare said.

Medics took one of the workers to a hospital for an evaluation.

A witness said one of the robbers was carrying some sort of long, thin object, possibly a rifle or baton, the sergeant said.