Updated, 8:46 p.m. | Several hundred protesters briefly shut down traffic at entrances to the Queensboro Bridge, the Triborough Bridge, the Brooklyn Bridge and the Manhattan Bridge and the Holland Tunnel and Queens-Midtown Tunnel this afternoon as part of a coordinated series of protests over the acquittal of three New York City police detectives in the fatal shooting of Sean Bell in 2006.

The Rev. Al Sharpton, who coordinated the protests, was among more than 200 people who were arrested by the police — nearly all of them in an orderly fashion — for blocking traffic. The protesters expressed outrage over a Queens judge’s decision on April 25 to acquit the three detectives — Michael Oliver, Gescard F. Isnora and Marc Cooper — over the November 2006 death of Mr. Bell, who died in a hail of police bullets outside a nightclub in Jamaica, Queens, hours before he was to have been married.

Mr. Sharpton and his National Action Network coordinated the protests, which were to include five locations in Manhattan and Brooklyn, as well as protests in Chicago and Atlanta.

The largest protest site appeared to be outside the New York City police headquarters in Lower Manhattan, where hundreds of protesters began gathering around 3 p.m. Mr. Sharpton emerged around 4:15 p.m., joined by Mr. Bell’s fiancée, Nicole Paultre Bell, as well as Joseph Guzman and Trent Benefield, two friends who were shot and injured along with Mr. Bell. Leading a large crowd, they gathered on a traffic island in Centre Street, in front of the city’s Municipal Building, and blocked the entrance to the Brooklyn Bridge. They sat down and prayed, blocking traffic, until the police began a mass arrest of protesters starting around 4:40 p.m. Police officers placed plastic “zip cuffs” on the wrists of the protesters, taking the men and women away separately.

Earlier in the afternoon, a smaller crowd of protesters gathered on the East Side of Manhattan near the entrance to the Queensboro Bridge. Around 3:30 p.m. they stepped onto the lanes of the bridge, blocking traffic for about 30 minutes. The Rev. Dock Johnson, pastor of Community Baptist Church in South Ozone Park, Queens, kneeling with both arms extended and wearing a pin-striped suit, a leather cap and sunglasses, led the protesters, who sat down in the middle of the traffic lanes. After they resisted police orders to disperse, the protesters — including Mr. Johnson — were placed in plastic handcuffs and arrested.

Also on the East Side of Manhattan, around the same time, 100 protesters marched east on 34th Street before turning north of Second Avenue. A group of about 40 formed a line across the entrance to the Queens-Midtown Tunnel and formed a line, chanting. They blocked traffic for about 10 minutes until about 20 were arrested; the remainder continued their protest but stopped blocking traffic.

Uptown, a group of about 150 protesters gathered on 125th Street, Harlem’s main thoroughfare, and briefly blocked traffic leading to the Triborough Bridge; several dozen protesters were arrested.

A crowd of about 200 people gathered in Brooklyn, many of them blocking the entrance to the Manhattan Bridge; a city official said that 23 were arrested. About 100 protesters marched toward the entrance of the Holland Tunnel and blocked traffic; about 13 were arrested.

-- An update to this preliminary City Room report is being prepared for the Thursday print editions. We’ll post a link when it is published. Reporting was contributed by Sewell Chan, David Giambusso, C. J. Hughes, Colin Moynihan, Sharon Otterman and Karen Zraick.