May Kifle, 20, is suspected of placing clothes on a stove and lighting the burner at a home in the 2700 block of Arbor Grove Lane in Santa Rosa around 6:15 p.m. Thursday, Sgt. Mike Lazzarini said.
Police and firefighters determined that the blaze -- which caused about $50,000 in damage -- was intentionally set by Kifle, who fled as police and firefighters arrived, Lazzarini said.
Kifle lived at the home with her parents and a younger sibling, but no one else was there at the time the fire began, Lazzarini said.
Around 4:30 p.m. Monday, police contacted Kifle at the Santa Rosa Junior College Library, where she was ranting and causing a disturbance, Lazzarini said. She is not a student at the junior college, he said.
Police arrested her on suspicion of arson, and she was booked into Sonoma County Jail.