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.

The National Guard has at times detained protesters in its deployment to Los Angeles, an official said Wednesday, as demonstrations against Immigration and Customs enforcement raids spread to other major cities.