KINSTON, N.C. (AP) _ Investigators finally entered the hulking ruins of a medical supply factory Saturday, even as the debris continued to smolder.
Despite the unsafe condition of some of the building, investigators went inside the remains of the West Pharmaceutical Services plant, said Peter O'Connor, a special agent with the federal Bureau of Alcohol, Tobacco, Firearms and Explosives.
Firefighters continued to pour water on smoldering areas.
``There's hot spots here and there, it's just mainly containing them,'' said Mike Morris of the Lenoir County Fire Command. ``It's going to smolder for days.''
The blast shot flames and debris high into the air and shook buildings miles away Wednesday. Some investigators have theorized that dust produced in the rubber-making process might have ignited somehow, but others have said it's too early to speculate.
Wearing white helmets and protective coveralls, the investigators brought along dogs who sniffed for evidence of accelerants and examined the patterns of damage, O'Connor said. He said they were able to rule out some causes for the explosion, but he declined to give detail.
The investigators got into the chemical mixing room, where the fire is believed to have started.
``The investigation should be completed in the next several days when we hope to have a preliminary cause and origin,'' O'Connor said.
About 130 people were inside the plant, and nine remained hospitalized in critical condition Saturday at the North Carolina Jaycee Burn Center in Chapel Hill. Three people were killed in the blast's immediate aftermath, and a fourth worker died of his burns Friday at the Chapel Hill center.
Dozens of relatives and friends came to a downtown funeral home Saturday to mourn Faye Wilkins, who died near the beginning of the disaster when she was trapped by fallen steel beams.
Wilkins, 50, and her estranged husband had two sons and a daughter and three young grandchildren. She had worked at West for 17 years.
Family friend Angela Brown said it has been hard for Wilkins' loved ones to accept her death and those of the others. ``A lot of people are mad that this had to happen to these people,'' she said.
William Gray, 51, and James Byrd, 60, were also killed outright. Kevin M. Cruiess, 22, died Friday.