(Portland, OR) -- An investigation is ongoing after a Portland Police officer used a shotgun to hit a man in the head. It happened yesterday while police were attempting to arrest a vehicular theft suspect. Police say the suspect was inside the car parked under the I-405 viaduct when officers approached and used their cars the block in the driver. The driver then allegedly used his car to push the police cars out the way, prompting officers to deflate the tires. Police say the man then tried to grab something under his seat, leading an officer to hit him in the head with a shotgun. Officers later learned the man was trying to grab a replica handgun. The suspect identified as 32-year-old Brian Bruman was booked into jail. A use of force investigation is underway into the officer's actions.