Investigators say the man stole the Oakland Fire Department vehicle around 10:45 a.m.
Carilyn Harris's niece told her to dial 911 after a confrontation with a man sitting inside of the engine.
"She asked, 'what you're doing here?' He said, 'I'm a helper, what do you need?' She was like, 'No, you're not a helper.' So she took her own actions and that's when he pulled off in a fire truck," Harris told ABC7 News.
Her nephew also saw the suspect
Another witness, Demaria Anderson described the suspect.
"He had civilian clothes, he was saggin' too, he had regular clothes on, he looked like he was mental a little bit crazy," she said.
All of this happened just moments after a crew left Station 23 in East Oakland, near Eastmont Mall.
The place was empty when the suspect got inside the locked building, found the keys to a rig, and busted out.
Battalion Chief Frank Tijiboy showed ABC7 News the damage to the door.
After the suspect stole the rig and tore through this door, it had to be fixed, which is why the station was out of service for about four hours.
Meantime, the wagon was blowing past drivers on I-80 in cell phone video obtained by ABC7 news:
Once in Vacaville, some 50 miles from Oakland, CHP ordered a spike strip be put out.
The firetruck hit the spikes, and eventually slowed down and rolled into a parked car near Nut Tree Plaza.
The suspect was immediately taken into custody.
Back in Oakland, sadness fills the fire station.
Battalion Chief Frank Tijiboy said, "Disappointing and let down this happened to our fire station. We are here for our community and to protect our citizens so I would say a little let down."
Officials say rig will take a few weeks to repair.