A man arrested in connection with a road-rage incident last week is suspected of using a cigarette lighter to spark a 20-acre blaze later the same day in the East Bay hills, the Alameda County District Attorney’s Office said Tuesday. Alfredo Bautista, 24, of Concord, was arrested after an incident Aug. 2 where he reportedly brandished a rifle at motorists. Bautista was found with a cigarette lighter in his pocket when arrested and has admitted to starting the Grizzly Peak fire and eight others in the area, according to UC Berkeley police in court documents filed Monday.