How did two white flags get set atop the Brooklyn Bridge? No one knows, not yet, at least. New York City police Tuesday were investigating how the two American flags that historically sit on top of the Brooklyn Bridge were replaced with white flags, which universally represents surrender, Fox News wrote on Tuesday.

The white flags, which sat atop the Brooklyn Bridge's 273-foot towers, were removed by noon. But many answers are still unknown: like how anyone was able to climb the bridge without being detected. It certainly indicated a serious security breach in one of the city’s most secured landmarks, the news site added.

Police are unsure who or what time the flags were put on top of the Brookyln Bridge, but they said there was a chance it was done legally. Brooklyn Borough President Eric Adams told the New York Post he was confident law enforcement would be able to find answers.  

"Political and social expression, whatever its message may be, has a place in our society, but not at the expense of others' security. I am confident in the NYPD's ability to investigate this matter," he told the news site.

According to the New York Daily News, construction workers were the first to notice the changed flags at 5 a.m. Tuesday.

Video surveillance showed five people crossing the bridge at 3:10 a.m., which is when authorities believe the flags were changed. The vandals apparently covered the Brooklyn Bridge lights with aluminum foil.

It’s believed the replacements were American flags bleached completely white. "You could still see the stars and stripes," a construction worker told the Daily News. "My first reaction was, 'This is where you land the plane. X marks the spot.' It was really scary."

Twitter users began to wonder about the incident after it remained unsolved more than 12 hours after the white flags were first noticed. "Brooklyn Bridge" was one of the top trending topics on the social media site.

More than 120,000 vehicles, 4,000 pedestrians and 3,100 bicyclists cross the bridge that famously connects Brooklyn to Manhattan every day, according to the city's Department of Transportation, Newsday wrote. 

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