Sparks from a malfunctioning utility pole caused a wildfire that spread over a ridge from Kalihi to Fort Shafter today, officials said.

Approximately 70 city and federal firefighters are battling the wildfire that started at about 9:30 a.m.

Firefighters and the Honolulu Fire Department’s Air One helicopter responded to the fire that started behind a parking lot of the Board of Water Supply base yard on Kini Place in Kalihi Valley.

Firefighters stopped the fire about 30 yards away from the fence line that borders Hauiki Homes, a public housing project on Meyers Street, according to Capt. Terry Seelig, a Honolulu Fire Department spokesman.

A private helicopter contracted by the Army also assisted in water drops to battle the blaze.

There were no evacuations.

Area power lines were de-energized as firefighters contain the fire. Darren Pai, spokesman for Hawaiian Electric Co., said the company is investigating what caused the malfunction.