Credit claimed for Brooklyn Bridge flags

• Two German artists say switch of flags above Brooklyn Bridge was "art project"


• Their claims are being taken seriously, two law enforcement officials tell CNN


• Mysterious white flags were spotted atop the Brooklyn Bridge last month


• NYPD Commissioner calls incident a "matter of concern"

New York (CNN) -- In the end, it might not be the DNA evidence collected high atop the Brooklyn Bridge or license-plate checks on the thousands of cars that crossed the iconic span overnight that solve the giant flag caper.

In the words of a pair of German artists -- Matthias Wermke and Mischa Leinkauf -- the replacement of the Stars and Stripes fluttering above the bridge with two massive white flags last month was nothing more than an "art project" by the two performance artists meant to deal with "questions of historical legacy and art in the public sphere."

In fact, the NYPD only learned of the artists' possible involvement after their story appeared on the New York Times website Tuesday afternoon.

Specifically, a law enforcement official said, the video the artists provided to the Times appeared to show the white flags from a position that would lend legitimacy to their claim.

The claims are being taken seriously, two law enforcement officials told CNN. It's unclear if the Manhattan district attorney will be able to or even attempt to extradite the men, who told the Times they would cooperate in the investigation.

In a statement, the artists called the project "White American Flags."

"They were careful to treat the bridge and the flags with respect and followed the U.S. Flag Code," the statement said. "The return of the original flags is in progress. Like an empty canvas, White American Flags invites many readings, multiple interpretations and projections."

At the time of the stunt, many New Yorkers wondered whether it represented an act of terrorism or an anti-American statement.

The American flags atop the bridge towers were replaced in the overnight hours of July 21 to July 22, and the white banner s were spotted early in the morning.

"White American Flags" was meant in part as a tribute the German-born American architect of the Brooklyn Bridge, John August Roebling, who left Germany in 1831 "in search of a better future in the land of freedom and opportunity," the artists' statement said.

As part of the investigation after the switch, intelligence analysts looked into any possible significance of the day that was chosen to see whether that may yield clues. It turned out to the 145th anniversary of the death of John August Roebling.

The claim of credit by the artists appears to have taken the NYPD by surprise.

NYPD Deputy Commissioner for Intelligence John Miller said at a news conference last month that the NYPD had video showing four or five people crossing the bridge just after 3 a.m. Within the hour, the light that normally illuminates the flag on the Brooklyn side of the bridge flickered and appeared to go out. A few minutes later the same thing occurred on the tower on the Manhattan side.

"At this time, it appears it has no particular nexus to terrorism or even politics," Miller said Tuesday. "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 the statement is."

Look's like art project was it.

"The city has always been a magnet for artists, a metropolis praised as 'the global center of creativity,' where new progressive art has its place," the artists said in their statement.

Who switched two flags atop the Brooklyn Bridge?

CNN's Poppy Harlow, Marina Carver and Rande Iaboni contributed to this report.