Three truck-driving schools in Wisconsin have been targeted by the Trump Administration as part of a broader crackdown on companies it believes are fraudulently training immigrants to get commercial driver's licenses.

The Wisconsin schools, one of which has been closed for months, were among 110 companies nationwide the U.S. Department of Transportation ordered to cease operations Aug. 31 because, the department alleges, they gave driver's licenses to people who later didn't pass roadside English proficiency tests.

The government is not alleging students from the 110 schools were illegally present in the U.S.

Here's what we know about the Wisconsin schools included in the crackdown.

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The schools are: On Your Way CDL Training in Milwaukee; CDL Pro School in Kenosha; and Tez CDL School in Sturtevant.

Ted CDL School closed "a long time ago," a representative of the company told the Milwaukee Journal Sentinel.

Neither On Your Way nor CDL Pro were aware they were being shut down Aug. 31. Representatives of both schools said they learned of the federal government's effort to shut them down from a reporter's phone call.

The government is specifically alleging the 110 schools trained students who, once licensed, later failed roadside English tests. It is not alleging the students were illegally present in the U.S.

The Trump administration, including Transportation Secretary Sean Duffy and Homeland Security Secretary Markwayne Mullin, announced the schools were shutting down as part of a multi-state effort to "root out fraud." It is also sending investigators to schools to look for rules violations and auditing third-party skills test providers.

The administration has framed its crackdown on truck driving certifications for immigrants as a safety initiative.

Since 1937, the federal government has required truck drivers to be proficient in English. That means they must read and speak English sufficiently to converse with the general public, to understand highway traffic signs and signals, to respond to official inquiries and to make entries on reports and records.

The written test people must take to get a learner's permit is generally in English. In Wisconsin, it's also available in several other languages, including Burmese, Russian, Serbian and Spanish. With the learner's permit in hand, people then can enroll in behind-the-wheel training, which is handled by the training schools.

From there, people take a hands-on skills test to get a commercial driver's license. That skills test, per federal law, must be conducted in English, and interpreters are not allowed.

This article originally appeared on Milwaukee Journal Sentinel: What we know about the Wisconsin truck-driving schools targeted for closure