Updated 6:17 p.m.
Alameda police and fire officials have ruled a suspicious fire that broke out at Alameda High School this morning as arson.
Capt. Jim Colburn told Alameda Patch that the classroom fire set off a smoke detector at around 3:26 a.m. When firefighters arrived at the scene, they found the fire to be on top of a counter in the classroom.
Colburn said Alameda Police investigators are further investigating the incident.
Alameda Patch will update this story as more information is made available.