A Norwalk police officer was struck by a police cruiser and a second person was injured after their car plowed into police vehicles while officers investigated a separate crash on Park Street early Thursday.

The crash happened around 1:01 a.m. when officers were first sent to Norwalk Green where a car crashed into a tree and the driver ran from the scene.

While investigating the crash, officers say another car driving in the area struck a police cruiser at the scene and the impact of the crash caused the vehicle to strike an officer standing in front of it.

Police say the officer was seriously injuried but that their injuries are non-life-threatening.

The driver accused of crashing into the police car was also injured and police say they appeared to be impaired.

Both the officer and the driver of the car were brought to Norwalk Hospital.

Police were at the scene for several hours investigating the crash and the roadway was closed until around 7 a.m.