MERRILLVILLE, Ind. (CBS) — A police-involved shooting occurred in the parking lot of a Planned Parenthood office in Merrillville, Ind. Monday afternoon, apparently over a parking citation.

One man believed to be a truck driver was shot and taken away in an ambulance after a police officer was hurt in a physical altercation.

Planned Parenthood said the officer was off-duty and working at the health center when a disturbance erupted that had nothing to do with the agency’s mission. A semi-tractor-trailer truck — driven by the person who may have committed a parking violation — sat idle at the property Monday afternoon as police investigated.

“An unfortunate incident occurred this afternoon in the parking lot outside of our Merrillville health center. An off-duty police officer, who also works as a security guard at this health center, was involved in an altercation with another person, allegedly over a parking citation, causing injury,” Planned Parenthood said in a statement. “We are assisting with an investigation by local authorities.”

The truck was expected to be impounded and later searched for evidence, said Robert Byrd, spokesman for the Northwest Indiana Major Crimes Task Force.