FERGUSON, Mo. (AP) — City leaders in Ferguson, Missouri, are pledging their full cooperation with a federal civil-rights investigation into their police department following the death of 18-year-old Michael Brown.

Attorney General Eric Holder announced the investigation into the department Thursday. St. Louis County also agreed to work with the Justice Department to improve training in use of force and crowd control.

The city of Ferguson issued a two-paragraph written statement vowing “our willingness to be transparent and forthright as we continue the process of earning back the trust of our residents and our neighbors in the St. Louis region.”

Brown, who was black and unarmed, was shot and killed on Aug. 9 by a white officer, Darren Wilson.

County Police Chief Jon Belmar says he initiated the “collaborative reform” and “welcomes the scrutiny.”

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