ST. LOUIS — Dorian Johnson, the man who was with Michael Brown Jr. when Brown was fatally shot by a Ferguson police officer last summer, has been arrested on suspicion of drug charges and resisting arrest, St. Louis police said.

Johnson was arrested on Wednesday and police are pursuing charges. The specifics of where and when he was arrested have not yet been released.

Johnson was walking with Brown on Aug. 9 when the two were approached by Ferguson Police Officer Darren Wilson. The encounter ended with Brown fatally shot and led to months of protests and unrest in Ferguson.

Johnson recently filed a lawsuit against the city, Wilson and former Police Chief Thomas Jackson.

The suit claims Wilson assaulted Johnson, violated his constitutional rights, and intentionally and negligently inflicted emotional pain during the encounter.

The lawsuit seeks damages, including punitive, of at least $25,000. It also seeks an injunction to prevent the city of Ferguson and its police from engaging in assault, unlawful arrest and excessive use of force.