San Bernardino resident James Boyd Rooks, 51, gave the teller a note demanding cash at 1:26 p.m. and pretended he had a weapon, and someone called 911, according to police.
Rooks was stopped without incident and was sent to the San Bernardino Sheriff's Department Central Detention Center. The FBI was notified of the bank robbery, police said.
Sisters Ysenia and Isabel Barajas said they were directly behind the suspect in line and saw him hand over a fake check for $2,000.
"It was scary," Ysenia, 20, said, still breathing heavily. "They (police) told us to get out of the way of the guns."
Isabel, 18, said there was nothing suspicious about the attempted robber and that he put up his hands as soon as police arrived.
"He looked regular, but kind of like a hobo," she said.
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