AUSTIN, Texas — Another 1,000 active-duty servicemembers have returned to their home bases from a deployment to the southwest border of the United States, bringing the number of troops on the ground there to roughly 3,150, Pentagon officials announced Monday.

There are 1,050 servicemembers in Texas, 900 in Arizona and 1,200 in California working with U.S. Customs and Border Protection, said Col. Rob Manning, a Pentagon spokesman. The reduction of active-duty forces along the southern border began last week when about 750 servicemembers began returning to their home bases. The Defense Department has not announced which units have returned to which installations.

The deployment to the U.S.-Mexico border began Oct. 31 and was intended to last through Dec. 15. With numbers peaking at 5,900, it’s unclear how many troops will remain through the extended mission scheduled to end Jan. 31. The original intention was to “harden” and protect the border as a caravan of Central American migrants traveled through Mexico to seek asylum in the United States.

The military will continue providing engineering and military police force protection at designated ports-of-entry in California and Arizona, but drawdown most forces in Texas, officials at U.S. Army North said.

About 2,300 National Guard soldiers are also deployed to the border to support a separate mission with Border Patrol agents.

During the deployment, military engineers have place about 70 miles of wire obstacles and movable barriers at 22 ports, military police units have conducted more than 10,000 hours of unit training and combined rehearsals with Border Patrol agents and military rotary wing aviators have flown more than 740 hours, officials at U.S. Northern Command posted to Twitter.

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