(Corrects typo in first paragraph)
By Dave Warner
PHILADELPHIA, March 24 (Reuters) - A cigarette left on an upholstered chair was the likely cause of a New Jersey shore motel fire that killed four people last week, according to a preliminary finding released on Monday.
The fire started early on Friday in a designated smoking area on the top floor of the two-story Mariner's Cove Motel in Point Pleasant Beach, the statement said.
"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 in a statement.
Although the motel's surveillance system was badly damaged in the fire, investigators said they were able to salvage some video footage that lead them to the likely cause.
In addition to the fatalities, seven people were injured, three critically, when the blaze destroyed the motel. One victim remains in critical condition and another is listed in stable condition, while the others were treated for cuts and burns before being released from area hospitals, prosecutors said.
James Gianuzzi, 52, who was treated for smoke inhalation, said he escaped after being awakened by someone knocking on his door.
Autopsies showed smoke inhalation as the cause in the four deaths, which were listed as accidental. One of the victims was identified as John Alberti, 45, of Keansburg, New Jersey. The three others were all from New Jersey but the coroner had not confirmed their identities.
Of those injured, Keri Anderson, 42, remains in critical condition and Melanie Deieso, 22, is listed as stable, with burns to her legs. Both are being treated at St. Barnabas Burn Center in New Jersey.
The seaside town of Point Pleasant Beach is a popular destination for millions of sun-worshippers who flock to the Jersey Shore every summer.
But about half of the 40 residents of the motel were using it as temporary housing after being displaced from their homes by Superstorm Sandy, which slammed the U.S. East Coast in October 2012.
Local authorities will be meeting with building code officials, the Medical Examiner's office and surviving guests to compile a final report, prosecutors said.
(Editing by Scott Malone, Gunna Dickson and Eric Walsh)