Two lieutenants were attacked during a protest on the Brooklyn Bridge on Saturday, Dec. 13. (Credit: Chris Nooney; CBS2)

NEW YORK (CBSNewYork) — The NYPD on Tuesday announced a $12,000 reward for information leading to the arrest of seven suspects, in connection with a clash between protesters and police on the Brooklyn Bridge on Saturday.

A video posted to YouTube shows the assault on NYPD lieutenants Philip Chan and Patrick Sullivan during demonstrations against the Eric Garner grand jury decision, CBS2’s Matt Kozar reported.

Chan suffered a broken nose, police said. Both lieutenants had bruising all over their bodies, Burrell reported.

As CBS2 Political Reporter Marcia Kramer reported, police on Tuesday released enhanced photographs of the suspects — four men and three women. An additional suspect was added Tuesday to the six suspects pointed the day before.

https://twitter.com/NYPDDetectives/status/544950054122168321/photo/1

Police said two of the men were in the group ere the key aggressors and face felony charges of assaulting a police officer. The other five were expected to face lesser charges.

“Male number two has a hat on and later on his hat falls off and he has a receding hair line. He’s seen kicking Lieutenant Sullivan,” said NYPD Chief of Manhattan Detectives William Aubry. “Male number three is the most disturbing as well as male number two. He pulls the officers down to the ground, and then he proceeds to run away.”