In May, federal agents arrested or turned away more than fifty thousand immigrants at the southwest border, according to numbers released by the Department of Homeland Security. Apprehensions of immigrants at the border were up 2 percent from the same time last year.
The leader of almost 4,000 Border Patrol agents in the Tucson Sector says problems can emerge almost anywhere along the boundary between the United States and Mexico, not just at ports of entry.
Tucson Sector Chief Agent Rodolfo Karisch said the agency's ability to completely control traffic of people and material is not always assured.
"I would say, 'fragile control,'" according to Karisch. "We've made tremendous efforts over the years here in Tucson, but the traffic can definitely come back."
Karisch admits it's hard to predict where the next issue involving movement of people and material on the border might happen.
"Years ago, we had problems in El Paso, that shifted to California, then to Tucson, then to the Rio Grande Valley," he said. "So, we always have to be prepared for that."
Karisch worked in law enforcement in El Paso, Texas before joining the Border Patrol in 1986. He took charge of the Border Patrol's Tucson Sector last August. See more about policing traffic at the border on Arizona 360, airing Friday at 8:30 p.m. on PBS 6.