By CBS3 Staff

CAMDEN, N.J. (CBS) – A fire tore through an abandoned apartment building in Camden overnight. Flames broke out around midnight Wednesday on the 3400 block of Cramer Street.

Crews arrived and found heavy smoke coming from the second floor.

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The fire quickly grew to two alarms before firefighters got it under control.

No injuries were reported but the fire chief says it was a dangerous situation for firefighters.

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“About two hours into the fire we had this massive explosion which was something that surprised all of us because we had been operating so long, the building is all open, so it didn’t seem like a typical smoke explosion from a backdraft,” Camden Fire Chief Mike Harper said. “So we will find out what happened there through the course of the investigation as time goes on.”

This is the same place where two men died in a three-alarm fire back in October.

Authorities charged a homeless man with arson in that case.

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