White Flags on Brooklyn Bridge View Full Caption

MANHATTAN — American flags were mysteriously replaced with white flags atop the Brooklyn Bridge's two towers Tuesday morning.

Police, including the NYPD's counter-terrorism and intelligence divisions, were trying to figure who hoisted the flags and were reviewing surveillance footage of the vandals in action, sources said.

Images of the white flags hit social media about 7 a.m. and police brought them both down about four hours later.

Webcam footage of the bridge shows the American flag still flying between 8 p.m. and 9 p.m. last night, but the white flags can been seen flying between 5 a.m. and 6 a.m. At approximately, 3:42 a.m. the light atop one of the tower goes out, footage provided by EarthCam shows. It's unclear if this related to the flag swap.

Department of Transportation bridge painter Nick Krevatas, 49, climbed the cables of the bridge about noon, a cigar tucked into the corner of his mouth, and began the 3-hour process of replacing the white flags with a new 12 by 8-foot flag.

It was not immediately clear how the white flags, which are usually a military symbol for surrender, got there.

Alarmed doors that give workmen access to the towers apparently were not compromised, leaving outside cable of the likely means to get to the flags, sources said.

Police maintain a 24-hour presence on the bridge, stationed in squad cars at access ramps and below the bridge to watch for suspicious vehicles, sources said.

Witnesses reported seeing NYPD counter-terrorism officers heading up the stairs to the bridge about 9:30 a.m.

But people were still allowed to walk across the bridge even as the police presence increased. Crowds gathered on the Manhattan side of the bridge.

"This is unbelievable. The gate they have to get past looks very flimsy. It's a very scary thought that someone would do this," said Donna Corrado, 51, as she crossed over the bridge to Brooklyn.

The Department of Transportation, which oversees the bridge, referred press inquiries to the NYPD, which did not have additional information.

The flag incident on the heels of two break-ins at 1 World Trade Center first in September when three parachutists plunged from the top of the tower and then when 16-year-old boy climbed to the top in March.

An artist also illegally installed a sculpture atop the Queensboro Bridge in March and was arrested for trespassing, according to the Daily News.

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