Officials anticipate the new arrivals could swell the migrant caravan in excess of 10,000 and will need to be housed for an extended period of time – which the Mexican government says it lacks the resources for.

The majority of migrants, who have been on foot for more than a month, are sleeping on a dirt baseball field at an outdoor sports complex in Tijuana by the newly-fortified barbed wire fence that separates Mexico from the United States.

Despite the growing numbers, the Pentagon will reportedly start withdrawing a portion of the 5,800 troops deployed at the border this week, with the rest of the unit packing up before Christmas.

“Our end date right now is December 15, and I’ve got no indications from anybody that we’ll go beyond that,” Army Lt. General Jeffery Buchanan, who is overseeing the deployment, told Politico.

Fox News’ Gregg Re, Greg Norman and the Associated Press contributed to this report.