Five of the people face aggravated sexual assault charges and the sixth person a charge for improper photography or visual recording.
The alleged incident, which occurred at the Emergency Service District Number 6 Volunteer Fire Department in Waxahachie on Jan. 20, 2015, involved the firefighters using a chorizo sausage to sodomize a trainee.
The arrest warrant affidavit states the trainee told authorities the firefighters looked for a broomstick before deciding to use the sausage in the assault, during which the trainee was held down.
Video of the incident shows the firefighters yelling and laughing, according to the affidavit.
The trainee threw up after the assault, according to the affidavit.
After the incident, the trainee had his clothes taken from him while he was in the shower. When he exited the shower one of the firefighters took his towel and the trainee had to run outside to his vehicle to get clothing from his car.
The arrests came after an investigation by the Texas Rangers at the request of the Ellis County DA.
Those arrested on sex assault charges include: Keith Edward Wisakowsky, 26, Casey Joe Stafford, 30, Preston Thomas Peyrot, 19, Alec Chase Miller, 28, Blake Jerold Tucker, 19.
Brittany Leanne Parten, 23, was arrested on a charge of improper photography or visual recording.
A Texas Department of Safety spokesman said the investigation remained ongoing.
According to the fire department's Facebook page, Alec Chase Miller is a lieutenant and was awarded Officer of the Year.
"We're not in the news much down here, so this is very shocking thing," said Ellis County Commissioner Paul Perry. "I think people were surprised and it really kind of goes beyond that. We're disgusted."
Waxahachie Fire Chief Ricky Boyd says the volunteer fire unit there is not affiliated with the city, nor do any of his staff work there. He says the arrests are an embarrassment to all fire service.
"We do not condone hazing in any sort of way," he said. "We do not allow that in any fashion, no matter what level it is, and we certainly find it appalling what is being alleged to have happened."
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