U.S. Marines will join National Guard troops on the streets of Los Angeles within two days, officials said on Wednesday, and would be authorized to detain anyone who interferes with immigration officers on raids or protesters who confront federal agents.

President Trump’s deployment of thousands of troops and Marines to Los Angeles is fueling concern that they have not been properly trained to interact with civilians.

Roughly 700 Marines from the Twentynine Palms base have been mobilized in response to protests and unrest in Los Angeles.