Life Time Fitness says it is conducting an internal investigation and is collaborating with local authorities in their investigation of a reported assault that took place last month at a club in Chanhassen, MN, where the company is headquartered.

The attack occurred on Sept. 16, and the case has been handed over to a Carver County (MN) prosecutor, Minneapolis TV station WCCO reported.

“This reported incident has been taken with the utmost of seriousness and concern,” the company said in a statement to Club Industry. “As should be expected, our immediate focus remains on the individuals involved with this matter. With our unwavering member experience commitment in mind, we remain confident in the security and surveillance measures we have in place at Life Time, not the least of which involves the programs and areas of our centers designed for children.”

Asked about the nature of the reported assault, Jason Thunstrom, vice president of public relations and corporate communications for Life Time, referred back to the company’s statement and reiterated that internal and external investigations are under way.

This is the third alleged assault case at a Life Time club reported this year. Last Thursday, three children who are alleged victims of sexual assault by former employee Anthony Webster, testified against him in a Collierville, TN, court. Last month, a former trainer at a Life Time club in Warrenville, IL, was arrested on sexual abuse charges. Robert Theodore is accused of having inappropriate sexual contact with a minor boy in a hot tub at the club.