A New Jersey motel fire that killed four people last week may have been caused by a cigarette left on a chair, officials say.

The fire damaged much of Mariner’s Point Motel’s surveillance system, but police were able to salvage enough footage to find a possible source of the blaze. Eight people were injured in the Point Pleasant Beach fire, but many were able to escape harm thanks to the quick thinking of customers who ran around knocking on doors.

“This is only the beginning of an intensive investigation aimed at answering the many questions surrounding all the circumstances that contributed to the tragic deaths, injuries and loss of property,” said Ocean County Prosecutor Joseph Coronato.

About 40 people were staying in the motel, but not all of them were tourists; some were residents who were displaced by Hurricane Sandy. Authorities have not released the identities of all of the victims but say they will be doing DNA tests to make positive IDs on some of the deceased. Smoke inhalation has been listed as the cause of death in all four cases.

One woman–whose name has not been released–stood in the running shower until help came, a smart move according to firefighters.

“One of our firefighters noticed her in a window,” fire chief A.J. Fox said. “She saved her own life, being in the shower (with the) water running.”

Officials say the cigarette–which was left on an upholstered chair in a designated smoking area–was probably the cause of the fire.

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