A Palestinian flag was hoisted onto the Manhattan Bridge Wednesday evening, following a nearby Pro-Palestinian march, police said.
The flag, which appeared draped from the lower level in photos on Twitter, was quickly taken down by police.
Yesterday's march traveled over the Brooklyn Bridge, police said.
When the flag was lowered onto the adjacent bridge, the crowd -- in the hundreds -- started to cheer, said Jenna Pope, 23.
"Some other people who knew about the march thought it would be a great visual while marching across the bridge," she said. "Everybody got excited about it. People started cheering and they were all pointing at it. They got a lot louder."
The march started in Brooklyn at about 6 p.m., she said, and concluded by One Police Plaza about two hours later.
Councilman David Greenfield called the flag "anti-Israel & anti-Semitic," blasting the police department on Twitter for allowing another unauthorized flag on the city's bridges.
"The dropping of another illegal flag on a major NYC bridge leads to the question of whether @NYPDnews is still capable of protecting NYC," he wrote.
It was not immediately clear who was responsible for lowering the flag.
Last month, the American flags atop the Brooklyn Bridge were replaced with white flags. A pair of German artists claimed responsibility for the stunt and said they did it to honor the bridge's German engineer, John Roebling, who died on July 22, in 1869.
Mayor Bill de Blasio called for them to be arrested as a result.