The acting head of Customs and Border Protection (CBP) warned Thursday that “super labs” in Mexico are flooding the U.S. with purer, cheaper forms of methamphetamine -- and that seizures of the deadly drug were up 90 percent last month compared with the same time last year.

Acting CBP Commissioner Mark Morgan sounded the alarm while talking to reporters about the October border numbers, which showed that while apprehensions of migrants at the border continue to drop, the agency still faces a crisis -- particularly when it comes to narcotics.

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CBP apprehended or deemed inadmissible over 42,000 migrants at the southern border in October, a 14 percent drop since September and 70 percent from the 144,000 encountered in May. Morgan hailed the results as a success for the administration’s approach to the border crisis, despite what he said was a congressional failure to act.

“As we’ve had to navigate unprecedented judicial activism from lower courts and congressional inaction...the numbers show this administration has and continues to take bold action to address this crisis, and the numbers show it’s working,” he said.

But Morgan said there is still a national security and humanitarian crisis at the border, and pointed specifically to deadly narcotics such as cocaine, fentanyl, heroin and meth still flowing across the border.

“Methamphetamine has seen a resurgence in this country,” he said. “Super labs in Mexico are taking over production and flooding the United States with cheaper and purer forms of meth.”

He offered grim statistics: In October, CBP seized over 9,700 pounds of meth, up over 90 percent from the same time last year. CBP also seized 284 pounds of fentanyl, an 84 percent increase over this time last year.

Morgan said that cartels and smuggling organizations are able to exploit not only the immigration system, but enforcement gaps as agents are pulled off the front line to deal with the humanitarian crisis. He also warned that the crisis affects every town and state in America, even those far away from the border.

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“Make no mistake, if your city, town or state has a meth problem, it came from the southwest border,” he said, before noting that the numbers show only what was seized, not what was actually getting through into American towns and cities.

Cooperation between Mexico and the U.S. has intensified this year, particularly over the summer in the form of the Migrant Protection Protocols (MPP), by which migrants are returned to Mexico to await their asylum hearings.

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Critics say the policy is inhumane and puts migrants in danger. But the administration argues it allows asylum claims to be processed quicker and reduces the pull factors which encourage migrants to make the dangerous journey north. It’s one example of regional cooperation with countries including El Salvador and Guatemala that officials say is stopping the migrant flows.

Morgan says those agreements are part of a broader administration strategy that has ended “catch-and-release,” the practice whereby migrants are apprehended and then released into the U.S.

"Migrants can no longer expect to be allowed into the interior of the United States based on fraudulent asylum claims," he said.