Workers removed the bodies of 6 workers after a chemical tank explosion in Washington state

Crews have recovered the bodies of six of the nine workers who were missing and presumed dead after a chemical tank explosion in Washington state, officials said Thursday.

The number of dead is 11, including three who are still missing. It is one of the deadliest workplace accidents in the US in recent decades.

Officials say a paper mill tank exploded and spilled more than 500,000 liters (1.9 million liters) of a highly toxic chemical mixture used to make paper at Nippon Dynawave Packaging Co. in Longview, a city along the Columbia River about 70 miles north of Portland, Ore.

Among the 11 victims is a grandfather who was described as always willing to help anyone and a young husband who was remembered as a selfless and caring person, according to friends who organized a fundraiser for the victims’ families.

Fire officials said Wednesday that the search for the missing workers will be slow and deliberate because of the dangers posed by the remaining chemicals.

Authorities said the cause of the crash is still under investigation. They have not released the names of those killed, but friends and relatives have begun confirming their names and posting online fundraisers to support their families.

Gilbert Bernal, a grandfather who worked as an electrician at the plant, was the first to be confirmed dead, said his friend Todd Cornwell.

“He was one of the most genuinely nice people you ever met. He would give you the shirt off his back if you needed it. He was always willing to help with whatever needed to be done,” Cornwell said.

CJ Doran, who was 26, was among those presumed dead, according to a GoFundMe post verified by the fundraising site.

He was the husband who was “the spiritual leader of their family, the joy of their home, and the breadwinner of the family,” the official said.

Other victims include John Forsberg, described as the father of two young children; Jared Ammon, who had two children and another on the way; and Braydon Finkas, an industrial electrician who, along with his longtime partner, Kaitlyn Kincaid, exchange students with people in need at their home in Cathlamet, Wash., according to friend Rex Czuba.

Finkas was always willing to help someone mow the lawn or buy a fresh draft beer in their small town, he said.

“He was a big part of the city,” Czuba said. “He really jumped into the community so quickly.”

The tank failure also injured eight people, including a firefighter. Others suffered burns or inhalation injuries, authorities said.

The Japanese parent company, Nippon Paper Group, said in a statement on Wednesday that it “expresses its condolences and sympathies to the bereaved families.”

Authorities said Wednesday that the spill did not contaminate the air or drinking water in the area near Longview, a city of about 40,000 people on the Washington-Oregon border.

The community, founded at the confluence of the Cowlitz and Columbia rivers by a Kansas City lumberman in the 1920s, has deep ties to the paper and lumber industries. Generations of families have worked at the mills, and many residents who spoke to The Associated Press have family members or friends connected to the Nippon Dynawave plant.

Crews are working to drain water from canals near the facility and purify it before pumping it into Columbia.

Some of the pollution has reached the river, but the US Environmental Protection Agency said there was no visible impact.