Denver police are investigating a crash that sent a person to the hospital with a broken leg Thursday morning. 

Police tweeted that officers were on scene of a crash involving a vehicle and three pedestrians in the 4800 block of Morrison Road just before 4 a.m. 

One person was taken to the hospital with serious injuries, according to the tweet. The other two pedestrians received minor injuries. 

Police say the driver was arrested at the scene for investigation of assault. 

Morrison Road was closed from Kentucky Avenue to Tennessee Avenue as officers investigated the crash. Police reopened the street just before 4:30 a.m.

Police haven't said what may have caused the crash. The investigation is ongoing.