PHOENIX (AP) — A Texas border crossing was closed to vehicles Monday, and traffic at an Arizona crossing was limited to shift more resources to illegal entries, U.S. authorities said in the latest sign of how fast-changing migration routes are challenging the government to keep up.

Customs and Border Protection said it was closing one of two bridges to vehicles in Eagle Pass, Texas, a town of about 30,000 people that, for a while last year, was the busiest corridor for illegal crossings. The agency is also reducing vehicle entries in Lukeville, Arizona, a remote desert crossing that has become a major migration route in recent months.

“The U.S. is continuing to see increased levels of migrant encounters at the Southwest Border, fueled by smugglers peddling disinformation to prey on vulnerable individuals and encourage migration,” Customs and Border Protection said in a statement. “As we respond with additional resources and apply consequences for unlawful entry, the migration trends shift as well.

Lukeville lies in the Border Patrol’s Tucson sector, which was the busiest of nine along the U.S.-Mexico border by far in October.

John Modlin, the sector chief, said Sunday that all sector social media accounts would be temporarily reduced in response to “the ongoing migration surge.”

“At this time, all available personnel are needed to address the unprecedented flow,” Modlin wrote on X, the platform formerly called Twitter. “The social media team will return once the situation permits.”

He returned a short time later to apologize for the “hastily written statement” and pledged transparency.

Staffing cuts to legal trade and travel are the latest response to demands for processing people who cross the border illegally, often to seek asylum. A major pedestrian crossing in San Diego was closed for weeks starting in September as authorities turned more attention to people who entered the country without permission.

While arrests for illegal crossing fell in October, September was the second-highest month on record.