Three boys playing with a lighter are under investigation as a possible cause of Thursday evening's Saugus brush fire that charred two acres, an official said Friday.

"Three 11-year boys came up to a firefighter at the scene and admitted to starting the fire," said Sheriff's Department Lt. John Hocking. "They were playing with a lighter."

But another possible cause was sparking power lines, Hocking said.

The boys were not detained and the sheriff's arson detail investigation was continuing, Hocking said.

The fire, reported about 6 p.m., was doused before 7 p.m. Thursday. It blackened two acres east of Seco Canyon Road, west of Tamarack Lane and north of Hazel Street.

No structures were damaged in the blaze.