Brown had been quiet about what his plans were with regard to Trump's announcement until now.
Instead, California's national guard troops will combat transnational drug crime, firearms smuggling, and human trafficking.
Republican governors in Texas, Arizona and New Mexico have committed at least 1,600 Guard members so far.
Texas governor says Guard impact 'meaningful'
U.S. Homeland Security Secretary Kirstjen Nielsen will head to New Mexico for an update on President Donald Trump's proposed border wall. Texas will continue to implement robust border security efforts to ensure the safety & security of our citizens. Democrats say a physical wall will not help the issue of illegal immigrants crossing into the USA, while Republicans say it's crucial for security.
Texas was quick to welcome the move, announcing that they would send 250 troops to their border.
But let's be crystal clear on the scope of this mission.
One Guard member was armed with an M4 rifle and used binoculars to peer across the river.
Nationwide Border Patrol Council president on how the Nationwide Guard will help brokers go after smugglers. Mexican children who had attended school on the US side of the border showed their passports and paid a toll to cross a bridge over the river and walk home to the Mexican community of Ciudad Miguel Aleman.
According to the governor, the number of people crossing the border has increased more than 200 percent over this time past year.
Monthly border arrests surpassed 50,000 in March for the first time since December 2016.
Some of those will be sent to the Rio Grande Valley, including Roma, Texas.
Inspectors at official crossings made almost 13,000 arrests in March, led by the Laredo, Texas, field office with more than 4,800 and the San Diego field office with about 3,800.