Civil rights groups are renewing calls for an independent investigation into the fatal shooting of a terrorism suspect accused of pointing a knife at police in Boston.

The Muslim Justice League and the Massachusetts chapters of the American Civil Liberties Union and the Council on American-Islamic Relations say key questions remain in the June 2015 shooting of Usaamah Rahim.

Boston police and FBI agents shot and killed him in a shopping plaza parking lot. They say he had ignored repeated orders to drop a 13-inch knife as he approached them.

Activists argued Thursday the confrontation should not have resulted in Rahim's death because terror investigators had placed him under surveillance long before.

Suffolk County District Attorney Daniel Conley announced Wednesday his office's investigation found no wrongdoing and would not be seeking criminal charges against the officers.