A relative state of calm in Los Angeles began to crumble early Sunday afternoon as demonstrators confronted federal authorities guarding a downtown detention facility where chaos erupted as National Guard soldiers deployed tear gas on an increasingly agitated crowd.

A man in a car uses his mobile phone as members of law enfocement stand guard on a road after curfew, as protests against federal immigration sweeps continue, in downtown Los Angeles, California, U.S.

By Brad Brooks, Omar Younis, Idrees Ali and Tim Reid LOS ANGELES (Reuters) -Hundreds of U.S. Marines were undergoing refresher training in riot and crowd control just outside of Los Angeles and will move into the city soon,