Beginning at 8 a.m. Tuesday, at least three northbound lanes at San Ysidro Port of Entry and one lane at Otay Mesa Port of Entry will be closed for the installation of barbed wire, barriers, barricades and fencing, according to U.S. Customs and Border Protection.
About 5,800 active duty troops are assigned to the border mission.
Central American migrants give a thumbs up to motorists who wave to them, as they begin their morning trek to reach the USA border as they leave Cordoba, Mexico, Nov. 5, 2018.
"Ever since I left home I knew it wasn't going to be easy", said Hernandez, who sobbed quietly as he thought of the two sons, Mateo and Steven, he left at home. Trump invoked the same national security powers he used to push his travel ban through and says he wants people to come to the USA legally.More news: Oil Crashes After Trump Says Prices Should Be 'Much Lower'
A USA official speaking on the condition of anonymity confirmed to ABC News that border authorities are girding for the first group of about 100 to arrive in Tijuana by the end of the weekend.
They thought other buses would be waiting for them to take them through hurricane-ravaged Nayarit to the neighboring state of Sinaloa, further north.
Indeed, migrants have hopped aboard so many different kinds of trucks that they are no longer surprised by anything. It is the second group to arrive there since Sunday, when about 80 LGBTQ migrants arrived by bus. Larger groups are expected to arrive in the coming days, human rights organisations said.
Jalisco Gov. Aristoteles Sandoval said Thursday the state had never agreed to transport them to Nayarit.More news: Palestinian factions, Israel reach Egypt-brokered cease-fire
A wide majority of about 63 percent of midterm voters in West Virginia said they support Trump's immigration agenda - calling it "just right" or "not tough enough".
Most appeared intent on taking the Pacific coast route northward to the border city of Tijuana, which was still about 1,350 miles (2,200 kilometers) away. The migrants have come about 1,200 miles (1,900 kilometers) since they started out in Honduras around October 13. Tijuana, in the Mexican state of Baja California, is at the westerly end of the border, around 17 miles (38km) from San Diego, California.
The caravan, which primarily includes people from Guatemala, Honduras and El Salvador, began with about 120 people and grew to about 7,000 at its peak, United Nations figures indicate.
Mexico has offered refuge, asylum or work visas, and its government said 2,697 temporary visas had been issued to individuals and families to cover them during the 45-day application process for more permanent status. It said about 533 migrants had requested a voluntary return to their countries.More news: Trump Prepares To Remove Homeland Security Secretary Kirstjen Nielsen