At least 250 people were arrested Thursday and seven police officers injured as Occupy Wall Street protesters took part in a "Day of Action," featuring rallies and marches throughout the city to mark two months since the start of the movement.

It all started when several hundred protesters made their way from Zuccotti Park to the New York Stock Exchange before the 9:30 a.m. opening bell.

Barricades were set up by the New York City Police Department to control the crowds, and only people with stock exchange IDs were being let past a certain point.

Police said five officers were taken to an area hospital when a demonstrator threw an unknown liquid at them, possibly vinegar.

It happened near Broadway and Wall Street.

The injuries were not said to be serious.

Police said two additional officers were injured later in the day when protesters at Zuccotti Park tried to remove barriers that have been set up since Tuesday's sweep.

One officer, 24-year-old Matthew Walters, received 24 stitches in his left hand after a demonstrator threw a star-shaped glass object toward him.

Another officer suffered irritation to his face after a demonstrator threw an unknown liquid, similar to an incident earlier in the day.

Both were treated at Bellevue Hospital. Mayor Michael Bloomberg and Police Commissioner Ray Kelly visited them.

"This object with glass in it was thrown at the police officer. It hit this officer, he made a defensive move with his hand and this is when he received the laceration," Kelly said.

Mayor Bloomberg said there were also reports of protesters flicking lit cigarettes at NYPD officers assigned to Zuccotti Park, which may have added to the scuffle.

"Police confiscated about a dozen mental devices comprising of metal sleeves wielded together and designed to accommodate individuals who planned to lock themselves to the entrances of Wall Street businesses this morning," the mayor said. "Some of these devices were found along the route of the protest march. Others were confiscated in a truck stop early this morning. None were actually used."

Despite the incidents, Bloomberg said the expected turnout for the protest was much lower than expected and that the city was more than prepared.

At one point, the protesters' presence wreaked havoc on many living in and around Wall Street as well as those trying to get to work.

"I think they need to take into consideration those that were supporting them as well. I think they're just being really selfish right now," said one Wall Street worker.

Despite that sentiment, protesters said were still working to get their message out.

"I'm concerned about Wall Street bankers ruining our country, ruining our economy, buying off our politicians," said one protester.

"I don't care about their crying that they can't get to work and steal more," said another.

The Scene At Zuccotti Park

NY1's Vivian Lee was present at Zuccotti Park Thursday for the violent clashes between protesters and police. She filed the following report, and video footage is included in the clip posted above.

There was a series of run-ins between Occupy Wall Street protesters and police in Zuccotti Park Thursday, and at least one protester was left bleeding.

It happened after someone flicked the hat off a police officer and was chased into the crowd.

As cries of shame rose from those watching, more protesters were rounded up by police. One police officer was cut in the hand.

It started with some protesters trying to remove barricades. Police rushed in to contain the crowd.

Officers attempting to put those barricades back angered some protesters, who pushed forward. NY1 noticed a couple of them being taken away.

The video posted above shows a scene in which NY1 news assistant John Hornbuckle could be seen trying to reach news assistant Nina Ibarra, who was shooting footage and got caught between fast-closing barricades as police pushed back against the crowd. Three officers pulled her out.

The day actually started peacefully at 7 a.m. with a rally across the street from the park followed by a march to Wall Street.

It was after their return from Wall Street that the tensions increased. The protesters attempted to return to Zuccotti Park, the symbolic center of the “Occupy” movement.

NY1 spoke with people who said this particular day, which marked two months of protest, was significant. Some said they used to work on Wall Street.

“I'd like to do my little, small part in seeking economic justice for this country,” said David Barack, a protester who said he is still working in the financial sector as a portfolio manager.

He said he had to join in protesting Wall Street excesses, a major gripe among those gathered here.

Protester Arrested After Macy's Threats Pleads Not Guilty

A demonstrator pled not guilty and was remanded on $25,000 bail over charges he threatened to attack Macy's in Herald Square.

Police say Nkrumah Tinsley, 29, was arrested Wednesday at Zuccotti Park after a video was posted online in which he said, “In a few days, you're gonna see what a Molotov cocktail does to Macy's."

Tinsley also said he was going to, "burn down the city."

Police say it was not clear if the Bronx man had the ability to make a bomb.

Tinsley was also arrested last month for allegedly assaulting a police officer during an Occupy Wall Street protest.