Richard Johnson, 62, of no fixed address, was charged with one count of public indecency, police said.
The woman approached the bus shelter at 175 Atlantic St. at about 9:30 a.m. and noticed a man was sitting there, said Sgt. Kelly Connelly.
"He said hello to her and proceeded to take his penis out of his pants and touch himself," Connelly said.
The woman saw a police officer doing a side job at a construction site and alerted the officer. Police were called and came to the scene.
"When they walked up to where he was sitting, sure enough he still had his penis out of his pants. But upon seeing the officers, he was nice enough to put it away," Connelly said.
Bond was set at $500 for Johnson.
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