SPARKS, Nev. (AP) — Firefighters expected to have full containment Monday night of a northern Nevada wildfire that forced evacuations in Sparks and burned dangerously close to a hospital.

About 130 firefighters got the flames under control Sunday evening after it had burned more than 4 square miles in the hills behind the Northern Nevada Medical Center.

About 20 homes were threatened at one time. And authorities canceled all ambulance trips to the hospital and directed all patients to neighboring hospitals in Reno.

No injuries were reported or structures damaged.

The fire was estimated to be 40 percent contained Monday afternoon.

The official cause of the blaze remains under investigation but Sparks Fire Marshal Bob King says lightning was reported in the area just before the blaze broke out shortly after 3 p.m. Sunday.