NEW YORK (CBSNewYork) -- American flags were once again flying on top of the Brooklyn Bridge Tuesday afternoon, after someone replaced the flags sometime overnight with what appeared to be whitewashed or faded versions of Old Glory.
NYPD Deputy Commissioner for Intelligence and Counterterrorism John Miller said police do not believe the incident was connected to any terror threat.
Miller said as of around 8:30 p.m. Monday, the American flags were still flying on the Brooklyn and Manhattan towers of the bridge. But around 5:30 a.m. Tuesday, construction workers noticed the white flags had taken their place.
Surveillance video revealed that around 3:10 a.m., several people were seen crossing the bridge – four or five of them in a group. Several minutes later, the light that normally illuminates the American flag on the Brooklyn side of the bridge flickered and went out, Miller said.
About 12 minutes after that, the light on the Manhattan side of the bridge also went out, he said.
By 7:30 a.m. Monday, calls about the rogue flags were coming in to police. The bizarre sight turned plenty of heads.
"I saw it on the walk over, but I didn't know what it was," a woman said.
"It seems pretty, I don't know, daring," a man said.
When members of the Emergency Service Unit went to the top of the bridge later in the morning to document the scene, they found two 20-foot by 11-foot flags on each tower, which appeared to be American flags with stars and stripes that had been bleached white.
Police also found large aluminum pans that had been affixed with zip-ties to cover up the lights that normally illuminate the flags.
Emergency Services officers took down the rogue flags by 11 a.m. Crowds gathered on the bridge and nearby sidewalks to watch as the officers climbed the cables to take them down from the towers.
Miller said the flag replacement operation appears to have been pre-planned, since someone had to compromise a locked gate and know the size of the pan needed to cover the light.
He said someone with experience climbing in construction or bridge work also may have been involved, and the culprit may have scaled the bridge before.
Police said a number of people had access to the area in the past few weeks, including construction workers and even people associated with the Fourth of July fireworks earlier this month.
Watch NYPD Commissioner Bill Bratton's Full News Conference
As CBS 2's Jessica Schneider reported, Miller also said someone scaled the bridge despite two police cars parked on either end of the span, and dozens of cameras monitored by the NYPD.
"We're going to look at the camera coverage from both sides to the bridge, from approaches to the bridge, to determine – what number of people are we looking at? What are they carrying?" he said.
Miller said police do not believe the flags were intended to be a threat.
"It appears to have no particular connections to terrorism or even to politics," Miller said. "This may be somebody's art project or even a statement."
But police Commissioner Bill Bratton said the matter was serious nonetheless.
"Needless to say, no matter what the motive was, that is a matter of concern," Bratton said. "I am not particularly happy about the event, and have charged Commissioner Miller to conduct a full and thorough investigation into the circumstances."
Miller emphasized that the white flag placement was not funny, and was not acceptable.
"We don't take these things lightly, or as a joke, or as art, or within the realm of speech," Miller said. "These are issues of trespass. They put themselves in danger. They put others in danger."
Miller said there has been no credible claim of responsibility and no indication of a message to be communicated with the white flags – whether one of patriotism or one of protest, WCBS 880's Rich Lamb reported.
NYPD's Miller: No Likely Terror Connection In Brooklyn Bridge White Flag Placement
Whoever placed the white flags will likely be charged with criminal trespass, malicious mischief, and reckless endangerment once apprehended, Miller said.
Miller said police are combing social media to search for information about who might have been responsible for the flag placement.
Meanwhile, Brooklyn Borough President Eric Adams was furious that someone was able to climb the bridge unnoticed.
"This is one of our landmarks, and during the time when the NYPD is in heightened alert, there's no time for fun and games or jokes," Adams said.
Many New Yorkers and tourists alike were baffled as they saw the white flags being taken down.
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"It's some kind of peace or surrender movement, right? It's weird though, it's crazy someone could get up there without anybody knowing," one man said.
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"Seems pretty daring to go up there and change the American flags," another man said. "I guess it could be a personal thing for that person, but I'm really not sure, honestly."
"We were wondering how you could climb up the bridge," one tourist from France told 1010 WINS' Juliet Papa.
Councilman Mark Weprin (D-23rd) also spotted the flags Tuesday morning, tweeting: "Why are there white flags on top of the Brooklyn Bridge?"
The flags had some asking on Twitter if New York City had surrendered.
The bridge is supposed to be one of the most secure structures in the city with cops in the area for much of the day, CBS 2's Don Champion reported. Signs posted near the bridge also say the area is under NYPD video surveillance.
Brooklyn Borough President Eric Adams issued a statement, saying "If flying a white flag atop the Brooklyn Bridge is someone's idea of a joke, I'm not laughing."
"The public safety of our city is of paramount importance, particularly our landmarks and bridges that are already known to be high-risk targets," he said. "We will not surrender our public safety to anyone, at any time. Political and social expression, whatever its message may be, has a place in our society, but not at the expense of others' security."
Public Advocate Letitia James also issued a statement, saying the incident "raises serious concerns about our safety as a city."
"I am deeply concerned that security protocols may have been breached. It is imperative that the New York Police Department review security procedures for our bridges and tunnels," she said. "There must be a full investigation into how a person, or a group, scaled the bridge and replaced the American flags without being noticed by the NYPD."
Last August, the NYPD announced it was beefing up security at city bridges after a flash dance party was held on the Manhattan Bridge and after three other security lapses, including a would-be Spider-Man climbing the bridge an abandoned vehicle being left on its span.
According to the Department of Transportation, which maintains the Brooklyn Bridge, more than 120,000 vehicles use the bridge every day. The American flags fly on top of the bridge year-round.
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