OAKLAND (CBS SF) — Oakland Fire Department officials deemed a fire that burned two structures and displaced nine residents in West Oakland on Wednesday afternoon accidental.

The two-alarm blaze was burning a vacant single-family home and a duplex when firefighters arrived at Eighth and Campbell streets. The fire was reported at 2:18 p.m.

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“It started in the rear of the main fire building under the unoccupied house,” fire spokesman Michael Hunt said.

The homeowner was having work done, according to the worker who remained on scene for the duration of the fire, Hunt said.

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Three of the nine displaced were children. No one was injured.

The worker was cutting pipe with a grinder and sparks ignited gas in the pipe.

“He couldn’t extinguish it,” Hunt said. “The house did not have sheet rock and the fire spread rapidly through the home.”

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