A man suspected in the killing of Denver Broncos cornerback Darrent Williams pleaded not guilty Wednesday to federal drug charges.

Willie DeWayne Clark is charged with conspiracy and distribution of cocaine. Clark sold drugs in the Denver area with a group of gang members, authorities say. Group members are suspected in 11 unsolved killings, including Williams' death, police have said.

The group is responsible for moving hundreds of kilograms of cocaine through the metro area, according to court testimony.

No one has been charged in Williams' death, but Clark's attorney identified him in a court document as one of three suspects.