US extends troop deployment at Mexico border

The Defense Department announced late Monday that it will be extending the U.S. military's support mission on the southern border with Mexico through September, amounting to a nearly year-long deployment of troops there.

Close to 5,000 troops, including forces from the National Guard, are currently stationed at the border after being sent in response to a request by President Donald Trump and the Department of Homeland Security in October.

The troops had been sent to harden key points of entry along the border in response to large migrant caravans that had been marching their way up from Central America to reach the U.S.

"In response to the December 27, 2018 request from the Department of Homeland Security (DHS), Acting Secretary of Defense Pat Shanahan approved Department of Defense assistance to DHS through Sept. 30, 2019," the Pentagon said in a statement.

"DOD is transitioning its support at the southwestern border from hardening ports of entry to mobile surveillance and detection, as well as concertina wire emplacement between ports of entry. DOD will continue to provide aviation support."

Last month, then-Secretary of Defense James Mattis extended the deployment of troops at the border, which was originally supposed to end on Dec. 15, to the end of January.

The Pentagon originally estimated the cost of the deployment at $72 million, but the amount could now be significantly higher.

Meanwhile, amid a partial government shutdown, Trump is demanding that any prospective funding bill to reopen the government include money to fund his border wall, which he initially vowed Mexico would pay for.

The ongoing shutdown became the longest closure in U.S. history Saturday as Trump continues to insist on funding for the wall, a demand Democrats have been staunchly resisting.

Some 800,000 federal workers are caught up in the impasse, with no end in sight.