U.S. Border Patrol Chief Mike Banks was in the Rio Grande Valley Friday to deputize more than 300 National Guard soldiers.

Those troops are now authorized to arrest migrants in the Valley.

Officials said they've just finished training on Title 8, the law they'll be enforcing. Any arrests soldiers make must be supervised by a Border Patrol agent.

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Lately, migrant crossings have been low in the Valley and across the border. 

"I will use every possible resource to secure our border and I will not be satisfied that our border is secure until we have operational control of our border, which means anyone that crosses is apprehended or no one crosses," Banks said.

The troops' authorization is good for just 60 days, unless it's extended, which Chief Banks said he does plan to do.