Tension is growing as military troops and National Guard units are being sent to reinforce the border crossing in Eagle Pass.
At a news briefing Friday Customs and Border Protection officials warned the 1,800 Central American migrants being housed across the border in Piedras Negras not to try and cross illegally, despite a long wait to be processed.
The Mexican government continues to keep the migrants inside a fenced-in warehouse a short distance from the border.
Texas DPS troopers, 250 military personnel and hundreds of National Guard members will help to reinforce the border and prevent anyone from crossing illegally.
“Part of our preparations include installation of temporary impediment measures on our bridges such as Conex boxes, Concertina wire and Jersey barriers,” said Paul Del Rincon of Customs and Border Protection.
The migrants want to request asylum, but the port of entry there can only process 16 to 20 people a day.
Border agents are warning them not to try to cross the Rio Grande, which a family with young children had attempted to do earlier in the day.
"Those children were rescued in the middle of the river because they got out into the middle of the river and they couldn't go forward and they couldn't go backwards. So, we had to rescue those folks, it is treacherous it is dangerous," said Louie Wayne Collins of Border Patrol.
Some migrants say they were lied to by smugglers who told them they would be allowed to enter the U.S.
At Friday’s briefing, Customs and Border Protection officials said migrants who have what's called "credible fear" of returning to their home countries will likely end up in detention facilities in the U.S.