The chemical that killed two men cleaning the inside of a tanker truck in Arizona last month has been identified, police say. 

The incident happened on August 29th at Danny’s Truck Wash near 101st Avenue and Roosevelt Street  in Avondale, Arizona. 

Since the time of the accident, investigators have identified the toxic chemical as sodium hydrosulfide – a chemical known to be deadly in high quantities.

According to AZ Central News, two men working at the truck wash were assigned to clean the inside of the tanker truck. The first man climbed inside of the tanker and fell unconscious shortly afterwards, prompting the second man to climb inside to help. The second man then fell unconscious as well. 

Firefighters then worked in full hazmat suits in the summer desert heat to extricate the two men from the tanker, leaving four of the firefighters with heat-related health issues that sent them to the hospital. 

The men were eventually pulled from the tanker and the two were pronounced dead on scene. 

No further information has been released. 

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