LOS ANGELES (NBC, KYMA/KECY) - A third straight day of protest began Sunday in Los Angeles, where crowds gathered by midday in downtown and Boyle Heights in protest of recent immigration raids .

They included demonstrators who marched from Boyle Heights who briefly dispersed outside the Metropolitan Detention Center after authorities deployed what appeared to be tear gas .

The marchers joined a crowd of about three dozen that gathered earlier outside the federal building, which is being guarded by members of the National Guard.

After the tear gas cleared, the crowd reassembled.

Dozens of protesters gathered at Mariachi Plaza in Boyle Heights as demonstrators were seen waving flags, holding signs before marching toward downtown.

About 300 National Guard members arrived in Los Angel

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