STANFORD (CBS SF) — Whatever hazardous materials were in a room at the Stanford Medical School where a fire broke out Saturday morning were consumed by the fire, a deputy fire chief with the Palo Alto Fire Department said.

Firefighters were working earlier to determine what hazardous materials were in the third floor room of the Pathology Department.

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But because the fire consumed the materials, firefighters haven’t been able to find out what those materials were and hospital officials haven’t been able to tell fire officials yet, Deputy Chief Catherine Capriles said.

The fire broke out at around 7:30 a.m. in the Edwards Building at 300 Pasteur Drive.

It started as a two-alarm fire but was upgraded to three alarms before firefighters evacuated an area around the room and extinguished the blaze.

No one was injured in the fire, which did not affect any hospital buildings where patients were being treated.

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Edwards Building at Stanford Hospital

Stanford Hospital – Edwards Building at 300 Pasteur Dr. (Google Street View)

But fire officials have closed the hospital’s main entrance, which is at 300 Pasteur Drive, Capriles said. Patients and visitors are being directed to enter the hospital through the emergency room entrance on Quarry Road.

The main hospital entrance was expected to be open again at about 12:30 p.m.

The cause of the fire is under investigation.

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