Washington authorities have recovered six bodies as of Thursday and believe three more bodies are still missing after a chemical tank implosion occurred at the Nippon Dynawave Packaging Company on Tuesday.

The incident occurred at approximately 7:15 a.m. local time and the tank contained white liquor, which is a mix of sodium hydroxide, sodium sulfide and disodium carbonate.

Authorities believe 11 people were killed in the incident, but only eight have been confirmed so far. The other two fatalities were reported earlier this week.

Longview fire chief Brad Hannig said he knew families of missing workers were anxious for clarity but recovery crews need to balance the desire for information with the risk they faced.

Firefighters have to wear protective gear and undergo decontamination and a health check each time they search because of hazardous conditions. Crews can only enter the explosion site a few times a day, according to the New York Times.

“It still continues to be a highly complex industrial hazard,” Longview battalion chief Matt Amos said. “It’s very labor intensive and takes a lot of personnel.”

The root cause of the implosion has not been identified.

Misty Severi is a news reporter for Just The News. You can follow her on X for more coverage.