A protest was held in Manhattan Thursday to demand a federal investigation of the Westchester County District Attorney's Office.

People at the rally said they want an investigation into the number of black men killed by police in Westchester.

Kenneth Chamberlain Jr. attended the rally and says they want the nation to know that police brutality exists in one of New York's richest counties. His father was fatally shot in his White Plains home by police, who had initially responded to a medical alert call.

A spokesman for the Westchester DA says each case was fully and extensively investigated and presented to a grand jury, which found the officers' actions justified. The U.S. Attorney's Office told News 12 that it had no comment.