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Wallis allegedly ran six brothels throughout Houston in different apartments, with 6-10 women in each.

Police said Wallis was paid $400 a week from each woman.

The arrest was part of 17 prostitution raids conducted by authorities. Twelve other people were arrested during the raids, including 37-year-old Tracie Tanner, an alleged accomplice.

The Houston Chronicle reported that Wallis allegedly used his flight school as a front for screening women who worked for him to make sure they had employment records that appeared legitimate.

Tanner was charged with felony aggravated promotion of prostitution. She made $5,000 bail.

If convicted, she faces up to 10 years in prison.

Wallis is out on $15,000 bail and is due in court next week.

"United holds its employees to the highest standard," United Airlines said in a statement to KPRC2. "We are assisting the authorities and have removed Mr. Wallis from his flying duties."

If convicted, Wallis could serve up to 20 years in prison.

This is the second reported incident of criminal activity by an airline worker in a week.

A JetBlue flight attendant was arrested Thursday when she turned herself in after dropping a bag of cocaine at LAX Friday and running out of the airport.