A couch that had been left on the lawn outside the Point Loma/ Hervey Branch Library on Voltaire St. was set on fire Thursday afternoon.
It was unknown why the couch had been placed at the location, an after-school gathering spot for local students of varying ages.
San Diego Fire-Rescue doused the flames that left the couch a tangled mess of springs and burnt material.
While there were reports of juveniles running from the scene, it was unknown who set the fire.
San Diego Police are working with library staff to identify those responsible.