Astotec explosion prompts injury probe as banned explosive details emerge

New details have emerged after Thursday’s explosion at the Astotec pyrotechnics company in Winzendorf, Wiener Neustadt district, ORF reported on Monday. The Wiener Neustadt public prosecutor’s office is investigating unknown suspects on suspicion of negligently causing injury.

A 45-year-old employee was seriously injured in the blast and subsequent fire. The company said he is now recovering. The incident was the second workplace accident involving fire at Astotec within a few weeks. The first, in late June, was linked by authorities to contaminated material containing the primary explosive potassium dinitrobenzofuroxan, known as KDNBF.

After the June accident, the Wiener Neustadt district authority ordered several measures on July 7. These included the immediate suspension of KDNBF production and use in serial manufacturing, the authority confirmed to ORF.

Astotec reportedly agreed to destroy the prohibited material. Production could only resume after an industrial regulatory amendment permit had taken effect. The authority said no such permit was in force before Thursday’s explosion and that Astotec had not contacted it about the matter.

Production and use of KDNBF therefore remained prohibited throughout the entire site on the day of the explosion, including any laboratory used for testing, according to the authority.

Employees told ORF that KDNBF had nevertheless continued to be produced for weeks, in some cases operating across three shifts, and that it was also being made on the day of Thursday’s explosion. The allegations have not been independently confirmed. The authority said Astotec had not informed it that production had continued after July 7.

Employees repeated the allegations on Monday, saying KDNBF had been produced and used to make initiator pellets for weeks. Astotec declined to comment on whether the authority had issued an order concerning KDNBF production and use when asked by ORF on Friday and again on Monday.

Astotec rejected allegations of systemic safety deficiencies. Managing Director Christopher Lill said the company operated in strict compliance with all legal and regulatory obligations and maintained high safety and quality standards. The company referred to regular inspections under the Seveso rules, an inspection in November 2025, emergency exercises with authorities and emergency services, and several months of cooperation with TÜV.

ORF again asked Astotec on Monday whether KDNBF had been produced between July 7 and August 20. The company said it would provide an answer no earlier than Tuesday.

The Wiener Neustadt public prosecutor’s office received a report on Monday and has opened an investigation against unknown suspects for suspected negligent bodily injury. An expert in fire and explosion investigations has been appointed.

Investigators believe the immediate cause of the explosion was a chemical reaction in a safety waste container in a laboratory. It remains unclear which substances reacted. The state criminal investigation office is investigating, and a final expert report is expected to take some time. Around 100 firefighters responded to the explosion and fire.