At 4:32 a.m., an employee of All Pro Bail Bondsman reported the arson at 323 Texas St., which also houses the Veterans Real Estate and Investment company, police Lt. Randall Boggs said.
The bail bonds employee said he heard a noise outside and saw a male suspect run toward the back of the building.
The employee also saw smoke coming from the roof, which was on fire when firefighters arrived, Boggs said.
The fire reached two alarms and was controlled at 5:06 a.m., a fire dispatcher said.
No injuries were reported.
Police found evidence of homemade incendiary devices, some of which were unused, as well as a getaway vehicle, Boggs said.
The suspect was described as a white male wearing all black clothing.
Anyone with information about the incident is asked to call Fairfield police at (707) 428-7300 or the Solano County Crime Stoppers line at (707) 644-STOP.