Two mysterious white flags set atop the Brooklyn Bridge on Tuesday morning have stumped local authorities, and now there’s word that they were American flags that had been bleached.

The lights placed on the bridge that illuminate the flags were covered with large aluminum pans, and surveillance video shows the lights appear to flicker and then go out; a little while later, the same thing happened on the Manhattan tower. However, the video didn’t show clearly who might have covered them or climbed the bridge. Authorities believe it’s someone with construction experience, and say they don’t think the act is tied to a terrorist organization.

“At this time, it appears it has no particular nexus to terrorism or even politics. This may be somebody’s art project, or it may be an attempt at making some kind of statement, but at this point it’s not clear what that statement is,” said John Miller of the NYPD.

Social media outlets blew up today after word got out, with several conspiracy theories making the rounds. Before it was determined that the flags had at one point been American, some thought the replacements were meant as a symbol for “surrender” or perhaps that the iconic U.S. version had been painted over as a commentary by an artist.

“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,” said Brooklyn Borough President Eric Adams.

The person (or persons) responsible for the flag exchange would have had to be quick and crafty, as there are always two police cars at each end of the bridge. Authorities say they are offering a $5,000 reward for any information which leads to an arrest, and say they are looking into putting NYPD cameras on the landmark.

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