Investigators are still on the scene where a man barricaded himself in a car, parked right across from the California Capitol.
The Sacramento Police Department's explosive devices team members used their robots to search inside the car.
Police announced about 7 p.m. that they had found a suspicious device in the vehicle and were in the process of rendering it safe.
Sacramento police said they received a call about 1:50 p.m. about a man sitting in his car, blocking traffic on L Street, just north of the state Capitol. He was honking and screaming out of his silver sedan.
The car had a lot of graffiti, as well as posters with religious and political rhetoric on them.
Within a few minutes, Sacramento police arrived on scene and began evacuating people dining at nearby restaurants.
California Highway Patrol helped the Sacramento Police Department secure the perimeter during the standoff.
CHP said the Capitol was not on a full lockdown. They cleared the north section of the building as a precaution. They moved an Assembly committee hearing to the Senate side and closed the museum.
"This incident took place on a city street. So our role is obviously the Capitol, and the grounds of the Capitol. And so we aided them in setting up the perimeter and trying to keep people away from the incident," CHP Officer George Granada said.
FOX40 spoke to an employee at the treasury building who said his entire building was ordered evacuated.
Police said for two hours they had their SWAT tactical teams and hostage negotiators trying to talk to the man.
They were acting with "an abundance of caution," moving the public back further every hour.
At this point, they are investigating this as a "person barricaded in a vehicle" incident. Police said there are no signs of it being a terrorist threat.
"We don't believe this is some part of a larger threat. All we know is this is a barricaded individual in a vehicle. We're not sure what his intentions are," Officer Matt McPhail of the Sacramento Police Department said.
At 4 p.m., the suspect, a young man wearing a black tank top and red sweat pants, stepped out of the his car.
He looked to be holding a cell phone in one hand and a piece of paper in the other. He walked backward toward officers, where he was arrested.
Since his arrest, police deployed robots to search the inside of the vehicle. At around 6 p.m., there was a boom that came from the scene.
Sacramento police said they exploded the trunk open. It was not a bomb. They said once the robot investigations is over, they will reopen all streets near the Capitol.
L Street finally reopened just after 9 p.m.