CALVERT COUNTY, Md. — An officer is in stable condition after a crash involving at least four cars in Calvert County, Maryland Thursday morning, officials said. 

Around 6 a.m., the on-duty deputy was sitting at a traffic light in his unmarked Sheriff Deputy’s car on Route 4 when he was hit from behind, causing a chain reaction. 

After the deputy was hit, his car struck the car in front of him and then that car crashed into the car in front of it. 

The deputy has not been identified, officials said.

The deputy was taken to the hospital where he is in serious but stable condition. Police said two other drivers were injured as a result of the crash. They were taken to Calvert Health Medical Center in Prince Frederick, Md. 

At this time, no additional information has been released. 

Officials have cleared the scene and reopened Route 4 northbound at Cox Road.

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