Military troops began arriving in El Paso, Texas, and San Diego, California, on Thursday evening following President Donald Trump’s decision to declare a national emergency at the southern border.

The additional support of 1,500 active-duty troops consists of 1,000 U.S. Army personnel and 500 Marines from Camp Pendleton in California who will get their assignments along the border upon arrival.

“This represents a 60% increase in active-duty ground forces since President Trump was sworn-in Monday,” Acting Defense Secretary Robert Salesses said in a statement late Wednesday.

Active-duty military personnel began arriving along the southern border Thursday evening after President Donald Trump declared a national emergency to address the immigration crisis. (AP Photo/Eric Gay, File)

“The National Guard currently has over 1,600 Guardsmen supporting the federal border security mission,” said Gen. Steven S. Nordhaus, chief of the National Guard Bureau. “In conjunction with our Joint Service partners, we are developing additional support options to meet USNORTHCOM, USTRANSCOM and Department of Homeland Security force requirements as this critical mission evolves.” 

Additionally, more than 4,100 Texas National Guard personnel remain on duty at the border supporting ongoing Operation Lone Star efforts. 

Some of the troops being deployed to the southern border were on call or actively working in support of the California wildfires, though they were released from that mission and are now being reassigned, the senior official added.

Fox News Digital’s Liz Friden, Stephen Sorace, Jennifer Griffin and Greg Wehner contributed to this report.