'Rogue' Ferguson cops used illegal and excessive force on protesters: lawsuit
Police advance through a cloud of tear gas toward demonstrators protesting the killing of teenager Michael Brown in Ferguson (AFP)

Four more people caught up in racial unrest in Ferguson, Missouri, that followed the police killing of a black teenager, have joined a lawsuit alleging illegal assaults and detentions by "rogue" police officers.

The amended complaint, filed Thursday in U.S. District Court for the Eastern District of Missouri, seeks approximately $60 million and claims police used "wanton and excessive force" as they dealt with protests after the Aug. 9 killing of 18-year-old Michael Brown.

The lawsuit, which expands an initial petition filed for $40 million in August, follows weeks of racial strife in the St. Louis suburb of Ferguson, where Brown was shot and killed by Ferguson police officer Darren Wilson. Brown was unarmed and was walking with a friend when they became involved in an altercation with the officer. Wilson, who is white, shot Brown multiple times and the teenager died in the middle of the street.

A grand jury is exploring charges against Wilson, and outrage over the killing has prompted protests, which have included some vandalism and looting. At times police have responded with riot gear, tear gas, rubber bullets and military equipment to quell the turmoil.

But the lawsuit claims police actions were illegal and unwarranted.

"The message we are sending in Ferguson is that we have zero tolerance for rogue police officers who endeavor to take the lives or violate the rights of law abiding citizens," attorney Reginald Greene, who is representing the plaintiffs, said in a statement.

Greene said the suit could be expanded to include several more plaintiffs.

Named as defendants are the city of Ferguson, St. Louis County, Ferguson Police Chief Tom Jackson, St. Louis County Police Chief Jon Delmar, Ferguson police officer Justin Cosmo, and other unidentified police officers.

Neither the city, county nor police departments had any immediate comment on the lawsuit.

One of the new claimants, Ferguson resident Antawn Harris, said he was recording police as they beat another man when police turned to him and shot him in the face with a rubber bullet. Harris had to be treated at a hospital, the suit claims.

Plaintiff Nathan Burns claims he was sprayed with mace while handcuffed on the ground, and had his head slammed into the pavement.

Other plaintiffs also said they were shot him with rubber bullets, beaten and sprayed with pepper spray with no provocation.

(Reporting by Carey Gillam; Editing by Doina Chiacu)