Customs and Border Protection commissioner Kevin McAleenan told the Senate Judiciary Committee Tuesday that the agency hit an important milestone last month

"November was the first month in recorded history where more people arrived from another country than Mexico," he said, noting that the No. 1 country last month was Guatemala.

Guatemalans seeking asylum in the U.S. — for the most part — must wait in Mexico, which has created logistical problems for everyone. A research group from the University of Texas at Austin found that those seeking asylum are now waiting for days at nearly all ports of entry. Paul Kuhne worked on the project at border cities across from Arizona.

"So before they can even get to declare their fear and get into the station, they’re often waiting a total of two weeks, some people are waiting eight, nine days," he said.

The asylum seekers are typically turned away from the port by CBP officers and then organized into line in Mexico by local police. During the Judiciary Committee hearing, McAleenan acknowledged that this so-called metering further dissuades migrants from staying in line and they then try to cross the border illegally to speed up the already long process.