Ten people in northern Oklahoma were hospitalized after reportedly being given insulin instead of flu shots Wednesday.

KTUL in Tulsa reports it happened at Jacquelyn House, a care facility in Bartlesville. Police say first responders arrived and found multiple people unresponsive. 

CNN reports eight of the patients are residents of the facility and two are employees. All of them ended up at the hospital.

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The pharmacist who administered the insulin was reportedly a contractor who was hired to go to the facility to give flu shots.

The cause of why the wrong medication was administered is under investigation.