At least 34 people were arrested after hundreds of protesters gathered in New York City on Tuesday night to march against police brutality. The march was organized by National Actions to Stop Murder By Police. Many of the protesters cited the deaths of Eric Garner in Staten Island and Walter Scott in South Carolina. The protesters marched from Manhattan's Union Square and across the Brooklyn Bridge where they partially blocked traffic. Scroll down for video . Hundreds of protesters gathered in New York City on Tuesday night to march against police brutality . Demonstrators climb on the Brooklyn Bridge during the protest against police brutality . The march was organized by National Actions to Stop Murder By Police . Stephen Davis, the Police Department's chief spokesman, said 34 people had been arrested by early evening . Many of the protesters cited the deaths of Eric Garner in Staten Island and Walter Scott in South Carolina . Organizers say Tuesday's protest was one of 28 being held across the country . Protesters tried to gain accress to the roadways of the Brooklyn Bridge, but they were blocked by police . Police began making arrests around 4:30 p.m. and by late evening at least 34 people had been arrested . Stephen Davis, the Police Department’s chief spokesman, said 34 people had been arrested by 6:40 p.m, reports the New York Times. Police say an off-duty police officer driving home on the bridge was assaulted by two protesters when he got out of his vehicle to investigate. Police say the suspects ran off after he identified himself as a police officer. He was hospitalized with injuries to his face and arm. Mayor Bill de Blasio released a statement condemning the violence - he said it was 'unacceptable and will absolutely not be tolerated.' Traffic was halted as more people gained access to the roads . Protesters were angered by fresh cases of police violence against unarmed black men in the United States . 'And any other person who might use the right to peaceful protest as cover to initiate violence, cause mayhem or incite disorder — whether against the police, the people or property of our great city — should consider themselves on notice that New York City will not stand for it.' Last year, two officers were assaulted on the bridge during a protest over Garner's chokehold death. Seven people were seen on amateur video pushing, kicking and punching the two officers. Five people were later arrested in that assault. Organizers say Tuesday's protest was one of 28 being held across the country. The protest started at Union Square for a 2 p.m. rally and more protesters joined during the march . Mayor Bill de Blasio released a statement condemning the violence - he said it was 'unacceptable and will absolutely not be tolerated'
The march was organized by National Actions to Stop Murder By Police .
Protesters marched from Manhattan's Union Square and across the Brooklyn Bridge where they partially blocked traffic .
Marched from Manhattan's Union Square and across the Brooklyn Bridge where they partially blocked traffic .
Police say an off-duty police officer driving home on the bridge was assaulted by two protesters when he got out of his vehicle to investigate .