Police wearing helmets and carrying shields early Tuesday morning began to clear Zuccotti Park in New York City, where protesters from the Occupy Wall Street movement have been camped since September.

NBC New York reported around 3 a.m., a group of protesters remain in the park (estimates vary from 40 to 100); they've locked arms, refuse to leave. Meanwhile, hundreds of others marched up Broadway.

Around 3:30, the last resisters, who formed a redoubt in the encampment's kitchen area, were arrested, reported Josh Harkinson of Mother Jones magazine. He tweeted that police used tear gas and pepper spray. Everyone I witnessed being arrested was resisting peacefully, he said. 

Police helicopters could be heard hovering all over Lower Manhattan, reported Anthony DeRosa of Reuters. 

New York City Councilman Jumaane Williams, who rushed to the scene to support the protesters, tweeted: I can report that @ydanis, [Ydanis Rodriguez] a #NYC Council Member, has been #arrested at #OccupyWallStreet & is bleeding from the head thanks to the #NYPD

Amid a massive police presence, reporters said they were being prevented from covering the dramatic scene. Ryan Devereaux of Democracy Now, a radio, TV and online program, tweeted: The NYPD are now setting up a pen for the press as far from the remaining protesters as they can place us.  

Williams tweeted: The #media is being shut out of #ZuccottiPark; clearly our leaders need to be reminded that #freedomofthepress is a right, #notanoption.

A CBS News helicopter was ordered out of the sky by the police, who said they needed the airspace, according to Anthony DeRosa of Reuters. 

Mayor Michael Bloomberg's office said the protesters should temporarily leave the park and remove their tents and tarps. The protesters said hundreds of police were mobilizing around the park and that the eviction of the demonstrators was in progress.

Police spokesman Paul Browne said the city and the owners of the park, Brookfield Office Properties, issued fliers to the protesters saying the park would be cleared for cleaning shortly after 1 a.m. 

Browne said 15 people had been arrested for disorderly conduct and resisting arrest.

The flier said the city and Brookfield had decided that the continued occupation of Zuccotti Park posed an increasing health and safety hazard to those camped in the park, the city's first responders and the surrounding community.

Browne said most people had left peacefully, but there was still a small group of people in the middle of the park refusing to leave. He said the protesters can return if they want after the park is cleared but without their tents and belongings.

Authorities set up bright lights at the park and sought to keep people away from the site as police surrounded it.

Samantha Tuttlebee, 35, from the Brooklyn section of the city, told Reuters she was volunteering at the protesters' medical tent at the park when the raid happened. She said she had not been living at the park.

I'm shocked. They put my arms behind my back. They are really violent, Tuttlebee said. We were trying to leave and they threw us out.

Samantha Tuttlebee, 35, from the Brooklyn section of the city, said she was volunteering at the protesters' medical tent at the park when the raid happen

Samantha Tuttlebee, 35, from the Brooklyn section of the city, said she was volunteering at the protesters' medical tent at the park when the raid happened. She said she had not been living at the park.

I'm shocked. They put my arms behind my back. They are really violent, Tuttlebee said. We were trying to leave and they threw us out.

Police on Monday moved into an encampment by anti-Wall Street protesters in Oakland, California, clearing out occupants and taking down tents, while in Portland, Oregon, police confronted an estimated 1,000 protesters on Sunday.

The protesters in Wall Street had said they hope on Thursday to shut down Wall Street -- home to the New York Stock Exchange -- by holding a street carnival to mark the two-month anniversary of their campaign against economic inequality.

(Reporting by Michelle Nichols, editing by Will Dunham)