More than 2,000 active duty troops dispatched to harden the U.S. border with Mexico are back at their home bases, the Pentagon said Monday.

Last week, the number of troops deployed in support of Customs and Border Protection operations along the southwest border was reported to be 5,200.

This week the number is down to 3,150, a drop of 2,050.

“The department will continue to assess force requirements to meet CBP, Customs and Border Protection needs,” said Col. Rob Manning, a Pentagon spokesman.

The troops were deployed to the border on the orders of President Trump in response to a caravan of South and Central American asylum seekers he described as an attempted invasion. Their mission consisted largely of reinforcing dozens of border crossing points with concrete barriers and laying miles of razor wire fencing.

The number of U.S. troops peaked at around 5,900, in early November, right around the time of the midterm elections.

By mid-November Army Lt. Gen. Jeffrey Buchanan told Politico all the troops would likely be home by Christmas because the support mission was nearly complete and scheduled to end Dec. 15.

But then DHS requested an extension until the end of January.

The Pentagon would not say if the remaining 3,000 troops would be there the entire month of January or if more would gradually be sent home.

“Be very cautious about timelines,” Manning told reporters, saying the number of troops would be commensurate with the requested level of support. “Whatever support the CBP and DHS needs is what we're going to provide them.”