McKINNEY (CBSDFW.COM) – McKinney Police have launched an internal investigation as to why it took eight months for the department to acknowledge a woman’s sexual assault allegations against a chiropractor, officials said Wednesday.

Dr. David Russell is charged with sexually abusing two teenage girls at his chiropractic clinic in McKinney.   Police say he met the students while volunteering at the Taylor Dance Studio, which is owned by his girlfriend.

On Monday, former dance instructor Carla Mullendore told CBS 11 she and another instructor went to police in February after a teenage girl told Mullendore about one of Dr. Russell’s treatments the girl felt was inappropriate.

Mullendore also contacted Child Protective Services in July,  which forwarded the complaint to McKinney Police.   But the police investigation didn’t begin until October.

A spokesperson for the police department says it has launched an internal investigation into why detectives never followed up.

In a statement to CBS 11 the department says, “we are working as expeditiously as possible to determine why they went unanswered.”

FULL STATEMENT BELOW:

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