New Report On Possible Cause Of Deadly Silver Springs Apartment Explosion

BALTIMORE (WJZ) -- The preliminary report has been released for an explosion and fire that killed seven and injured dozens last year at a Silver Spring apartment.

Some questions now have answers, but a big question still remains.

One year ago, an explosion and fire blasted apart the Flower Branch Apartments in Silver Spring.

Firefighters managed to rescue some trapped by the flames, and rushed three dozen injured to area hospitals, but seven residents were killed when a large section of the building gave way beneath their feet:

"Ah, it just collapsed man. There was no getting out of that," one witness said.

Last November, survivors filed lawsuits to, as one lawyer put it,"finally give us a straight answer to this tragedy."

ATF and NTSB investigators are still seeking a definitive cause, but a preliminary report makes some findings.

Investigators say no gasoline was spread inside the building, and there was no drug lab that could have caused a blast.

Natural gas odor was reported shortly before the explosion, but firefighters found no positive hits for gas with detection meters.

But it is known a build up of natural gas in a basement storeroom fueled the explosion.

There is now a theory how the gas collected.

A vent pipe was found disconnected, which would have bypassed a safety feature to clear gas from the basement.

But the report finds "the person who disconnected the vent pipe, as well as his or her intentions of doing so, are as yet undetermined."

A mystery to be solved for a night hard to forget.

"Even though the building is gone, the memory will always be there," said neighbor Aita Flemming.

Final dollar loss from the explosion and fire is still not determined, but is expected to be at least $1 million.

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