A 3.4 million-litre tank that was about 60% full and contained a corrosive substance imploded, in what officials have called an "absolute tragedy".

The implosion of a chemical tank in southwestern Washington state on Tuesday injured at least 10 people, while an undisclosed number of others were killed or remained missing, authorities said.

The implosion of a chemical tank at a pulp and paper mill in Washington state injured at least 10 people, while an undisclosed number of others had been killed or remained missing, authorities said.

A chemical tank rupture at the Nippon Dynawave Packaging facility in Longview, Washington resulted in multiple critical injuries and at least one fatality, ABC News reported on Tuesday, citing authorities.

One person is dead and nine others remain unaccounted for after a chemical tank holding nearly a million gallons of a corrosive liquid imploded at a Washington paper mill, authorities said. Nine others were injured in the spill, some severely. Emergency responders were still working on recovery efforts at Nippon…