He was visiting a restaurant in the St Louis suburb when Missouri State Highway Patrol Captain Ron Johnson met with him.
Johnson has been overseeing the protests after several nights of unrest in St Louis stemming from the August 9 shooting of 18-year-old Michael Brown.
Holder then left Ferguson and was on his way to St Louis to meet with the FBI and others involved in the independent federal investigation.
Earlier in the day, the attorney general met with community college students to discuss their own interaction with local police.
The St Louis County prosecutor’s office has started to present evidence to a grand jury investigating the shooting. It is likely that evidence will be presented through to mid-October.
Separately, it has been reported the officer who shot the teen, 28-year-old Darren Wilson, who has been placed on leave, suffered “a serious facial injury” in the altercation before firing the fatal shots.