Brown announced the deployment in a late afternoon message to the media.
The announcement comes as President Trump has been accusing Brown of trying to back out of sending the National Guard troops to the border.
RELATED: National Guard Colonel denies rejecting plan to send troops to border
Brown says the guard will not enforce immigration laws or participate in the construction of any new border barrier.
The personnel will deploy within the state, along the coast, and at the border.
RELATED: Gov. Brown letter about National Guard troop deployment (PDF)
Some members will deploy before the end of the April and the mission will continue until at least September 30, 2018.
The text of the order issued by Brown is below:
April 18, 2018
GOVERNOR'S GENERAL ORDER NUMBER 2018-01
In response to the request from the Secretaries of Defense and Homeland Security, and consistent with my April 11, 2018 letter to Secretary Nielsen and Secretary Mattis, I issue the following General Order under sections 146 and 365 of the California Military and Veterans Code and in accordance with article V, section 7 of the California Constitution as the Commander-in-Chief of the California National Guard.
You shall call into active service up to 400 service members of the active militia, under section 502(f) of Title 32 of the United States Code, as needed to:
- Combat the non-linear threat of transnational crime that extends to areas of California beyond the U.S.-Mexico border;
- Disrupt transnational criminal gangs and human traffickers and illegal firearm and drug smugglers;
- Interdict illegal firearm and drug shipments crossing both directions of the U.S.-Mexico border and through coastal and offshore routes;
- Execute counterdrug and counter-narcoterrorism operations crossing both directions of the border and through coastal and offshore routes;
- Coordinate with federal officials to deploy personnel and equipment where needed to fulfill this mission;
- Coordinate with The Adjutant General of any other state as needed to fulfill this mission;
- Arm military personnel with issued military weapons during this mission only when you or your designee determine there is a mission requirement for doing so; and
- Ensure all California National Guard forces participating in this mission comply with the California National Guard's Rules for the Use of Force.
California National Guard service members shall not engage in any direct law enforcement role nor enforce immigration laws, arrest people for immigration law violations, guard people taken into custody for alleged immigration violations, or support immigration law enforcement activities. California National Guard service members shall not participate in the construction of any new border barrier.
You shall decline missions that would compromise the state's ability to respond to state emergencies, missions that would exceed the mission scope and limitations outlined above, or missions that do not meet a valid state and/or national security interest.
This order will remain in effect until September 30, 2018 unless further modified or rescinded in writing by me.
Edmund G. Brown Jr.
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