SAN ANTONIO — The top U.S. border official said Wednesday the number of people encountered and apprehended at the southern border will top 100,000 in March, the highest amount reported in one month in 12 years.

"Two weeks ago, I briefed the media and testified in Congress that immigration was at the breaking point. That breaking point has arrived this week at our border," Customs and Border Protection Commissioner Kevin McAleenan told reporters in El Paso, Texas, Wednesday.

"We are now on pace for more than 100,000 apprehensions and encounters with migrants in March, with 90 percent — 90,000 people — are instead almost guaranteed to remain in the U.S. indefinitely, regardless of the merits of their immigration or asylum claim," he said.

The border chief pointed to two years ago, when 16,794 people were arrested or deemed inadmissible for entry at border crossings. That number has slowly crept up over the past two years and increased an additional 24,000 since last month as Central American families increasingly travel to the U.S.-Mexico border.

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McAleenan also warned that those coming to the U.S. to seek asylum now face a two- to five-year wait because of the recent surge of families and lack of court and immigration officers to process all of the claims.

"The last time we had crossing numbers on this level, they were almost all single adults form Mexico that could be swiftly repatriated," he said.

Edgar Ramirez, the Department of Homeland Security's Mexico attache, told attendees at the Border Security Expo this week a Mexican adult who has been apprehended while illegally entering the country takes about 15 minutes for Border Patrol agents to process. An adult from a Central American country takes 90 minutes to process.

A family of at least two people from a country other than Mexico takes on average four hours to process.

Roughly 60,000 of the 100,000 people apprehended or encountered at the southern border are families.

A total of 396,000 people were arrested at the southwest border in 2018. Most families and unaccompanied children have been arriving in the Rio Grande Valley Sector of Texas, Yuma Sector of Arizona, and El Paso Sector of Texas, though it includes New Mexico.

McAleenan said requests to Congress to pass legislation and funding that it says would curtail the surge of people illegally crossing and arriving at ports of entry have gone unanswered, prompting CBP to adjust its own resources.

In fiscal 2017, CBP documented two groups of 100 people or more. The number of group apprehensions jumped to 13 in 2018 and have spiked to 93 just in the first six months of fiscal 2019.