[UPDATES BELOW] Shortly after 1 a.m., the NYPD swooped into Zuccotti Park to evict the Occupy Wall Street encampment that started at the site almost two months ago. Police are prohibiting press from getting near the park, but one protester, Sam Wood from Farmingdale, NY, tells us he left park around 2:45 a.m. because, "I decided it was a bad idea to stay in the park and I can do more out here than in there." Wood, who had been there since the occupation began, says he left after seeing three people arrested, but says 50-60 protesters defiantly remained in the park with arms locked around the kitchen.

Because press is being kept blocks away from the park, it's difficult to confirm what exactly is happening. Reuters' Anthony DeRosa says the CBS News desk told him their helicopter was forced by the NYPD to leave the airspace above Zuccotti Park. Animal New York witnessed an NYPD officer try to "yank" the press pass off an NBC reporter on Cedar Street; "it didn't come off so he told him to remove it at once."

Earlier this morning, the Mayor's Office tweeted, "Occupants of Zuccotti should temporarily leave and remove tents and tarps. Protestors can return after the Park is cleared." But protesters are being told they won't be able to return with tents and other personal belongings, and the new park rules are custom-designed to make the occupation less tenable. We're told the NYPD is cutting up tents and structures with box-cutters and saws, while some protesters remain chained to trees inside the park. According to Occupy Wall Street, at 3 a.m. some 400 protesters were still remaining in the park "after many arrests." The NYPD can be heard announcing through megaphones, "You have been warned to leave the park. Take your belongings and leave and you will be subject to arrest."

Here's a Livestream which is streaming fitfully:

UPDATE: Here's video of a violent clash between protesters and police:

And here's video from inside the park:

Update 3:52 a.m.: Witnesses inside the park say the NYPD is pepper spraying, tear-gassing, and forcibly removing the remaining protesters who surrounded the Occupy Wall Street kitchen.

Update 4:05 a.m.: Some protesters appear to be headed to Union Square Park. Animal New York managed to get to Zuccotti Park, and has published some great photos from the scene, including a shot of NYPD Commissioner Ray Kelly overseeing the surprise raid.

Update 4:15 a.m.: NYPD workers and Department of Sanitation workers clearing the park reportedly threw out some 5,000 books from the Occupy Wall Street library, which had just been transformed into a more permanent structure under a tent (with funding from Patti Smith).

Robbins is at Fulton and Broadway and reports that the NYPD is dividing protesters onto multiple corners and sidewalk, as part of a tactic to divide them and prevent a larger march from gathering.

Update 4:30 a.m.:The Observer reports that City Councilman Ydanis Rodriguez was arrested, and there is an unconfirmed report that Rodriguez was beaten. His press secretary David Segal tells The Observer, “City Hall knows that he has been arrested. They have put in a call to the NYPD to see his status." Segal could not confirm that Rodriguez was injured.

Update: 4:45 a.m.: There are approximately 200 protesters currently at Foley Square, according to reports on Twitter. They're discussing the next move.

Update 5 a.m.: The NYPD confirms approximately 70 arrests during the park-clearing, with one man hospitalized with breathing problems. (Witnesses said the NYPD used tear gas, and a Livestream from Zuccotti Park showed what appeared to be smoke, but that's unconfirmed.) The AP reports that before the raid, notices given to the protesters said the park "poses an increasing health and fire safety hazard to those camped in the park, the city's first responders and the surrounding community."

Update 6:30 a.m. Mayor Bloomberg has released a statement regarding the eviction of Zuccotti Park. Bloomberg says it was "taken at this time of day to reduce the risk of confrontation in the park, and to minimize disruption to the surrounding neighborhood." He goes on to say, “From the beginning, I have said that the City had two principal goals: guaranteeing public health and safety, and guaranteeing the protestors’ First Amendment rights. But when those two goals clash, the health and safety of the public and our first responders must be the priority."

Also notable:

We have been in constant contact with Brookfield and yesterday they requested that the City assist it in enforcing the no sleeping and camping rules in the park. But make no mistake—the final decision to act was mine.

(Emphasis ours.)

Towards the end of the release, the mayor notes, "Protestors have had two months to occupy the park with tents and sleeping bags. Now they will have to occupy the space with the power of their arguments." Read the full statement here.

Update 7:25 a.m.AnimalNY has posted video of the NYPD's final push to remove the protesters who locked arms (and necks) in the center of the park around 3 a.m.

Update: In a press conference after 8 a.m., Mayor Bloomberg said the decision to evacuate the park was "mine and mine alone" and, "For two months they have been allowed to use sleeping bags and tents. Now they will have to use the power of their arguments." However, a judge issued a temporary restraining order against the city, the NYPD, Brookfield Properties and other agencies to allow protesters back into the space with their belongings—and the city has decided to defy that order. Protesters marched in lower Manhattan, trying to retake Zuccotti, and also attempted to take Duarte Square, a park at 6th Avenue and Canal Street.

(Reporting by Christopher Robbins)