WASHINGTON – The Pentagon will send a fresh deployment of active-duty troops to the southern border at the request of officials from the Department of Homeland Security.

Late Monday, the Pentagon also announced that deployments of active-duty troops would extend through September.

The new contingent of troops will include combat engineers to fortify border crossings and aviation units to help ferry Border Patrol agents, according to a Defense Department official who was not authorized to speak publicly.

The troops will also help with surveillance at the border, according to the Pentagon statement.

The new deployment has been anticipated since Homeland Security officials made the request to the Pentagon for additional resources late last month. There are about 2,350 active-duty troops and an additional 2,200 National Guardsmen at the border.

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The troops, by law, do not have law enforcement duties.

The authorization for active-duty troops, sent there by President Trump before the mid-term elections, had been set to expire Jan. 31. The Department of Homeland Security requested the extension of deployments on Dec. 27.

Last week, the White House requested options from the Pentagon to build barriers at the border should Trump declare a national emergency. Under such a declaration, the military could tap funds for construction projects approved by Congress but not yet spent.

Trump traveled to the border in Texas last week. He was accompanied by the commander of the U.S. Army Corps of Engineers, Lt. Gen. Todd Semonite.