By CBS Baltimore Staff

BALTIMORE (WJZ) — Inmates set at least five fires in a Baltimore prison Sunday evening, according to the Office of the State Fire Marshal. More than 30 people were treated for smoke inhalation.

Baltimore Fire Department units responded to the Maryland Reception, Diagnostic and Classification Center in East Baltimore around 7:40 p.m., where correctional officers said there was a fire on the fifth floor.

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Firefighters found heavy smoke conditions on the fifth floor and extinguished the fire within minutes. Officials said 28 inmates were treated for minor smoke inhalation, while three inmates and a correctional officer were hospitalized. Their condition is unknown at this time.

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According to Deputy State Fire Marshals, three fires were set in the common area of the fifth floor. Paper products, clothing and a plastic rolling food cart were set alight.

While investigators were on the scene, inmates on another floor reportedly set two more fires, using including clothes and another food cart. Firefighters with investigators on the scene helped extinguish the second fire quickly, officials said.

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An investigation is ongoing into the arsons. Charges will be filed after consultation with the Baltimore City State’s Attorney’s Office, the fire marshal’s office said.

CBS Baltimore Staff