Officials in Tainan have traced the illegally dumped hazardous material behind a deadly fire and explosion, bad news for the landowner and waste operators now facing criminal and environmental charges.

• Police identified the landowner, the people who dumped the waste, and the middlemen who arranged it at the Annan District site.
• The main person involved owns several companies, including a hardware business registered in Kaohsiung — not a construction firm.
• Fire investigators found aluminum-magnesium alloy, waste oil, and material that reacts violently with water, which made the blast far bigger.
• Crews arriving overnight faced a fire already out of control, followed by a huge explosion cloud that forced them back to a safe distance.

Outlook: Prosecutors and environmental regulators will keep building the case, with charges expected over the illegal storage of dangerous material.