An Ohio State Highway Patrol trooper was killed while assisting a disabled vehicle in Canfield on Thursday. 

In a post on social media, the Ohio State Highway Patrol said Trooper Nicholas P. Cayton was in his cruiser when it was hit by the driver of a semi-truck on state Route 11 south, killing him. Authorities said he was assisting a disabled commercial vehicle at the time of the crash in Mahoning County. 

"Today, the Patrol lost a member of our family. This is a tragedy for the Ohio State Highway Patrol and the Ohio Department of Public Safety," Ohio State Highway Patrol Superintendent Colonel Charles A. Jones said in a post on Facebook. "Our prayers go out to the Cayton family during this difficult time."

CBS affiliate WOIO reported that a truck driven by a 35-year-old man crashed into the back of the trooper's cruiser, which then crashed into the back of the disabled vehicle. The driver of the disabled vehicle was also hit as he stood outside. He was flown to a local hospital. His condition was not immediately known. The 35-year-old man was not injured. 

The crash, which happened around noon on Thursday, is under investigation, WOIO reported. Ohio Gov. Mike DeWine said Clayton's death is a "heartbreaking loss for his family, OSHP, and all Ohioans."

"Fran and I extend our deepest condolences to Trooper Cayton's family, friends, and colleagues during this difficult time, and we will keep them all in our prayers," the governor went on to say in a social media post. 

DeWine ordered flags across Ohio to be flown at half-staff in the trooper's memory.