Nikola said it suspected foul play behind the fire last month. The June fire affected multiple trucks but caused no injuries.
“Foul play is suspected as a vehicle was seen in the area of the affected trucks just prior to the incident and an investigation is underway,” the company said in a tweet that day.
But foul play has not yet been confirmed by the Phoenix Fire Department or Nikola.
“The investigation is still ongoing by both the Nikola engineering team and a contracted third party. An update on the findings will be provided once the investigation concludes,” a Nikola spokesperson said about the June fire.
The third party of the investigation has not been shared publicly.
The fires come as the company pivots its business toward hydrogen-powered trucks. Nikola announced 270 job cuts last month in Europe and North America. And earlier this month Nikola said it will liquidate the assets of Romeo Power, an EV battery maker it acquired less than a year ago for $144 million.
Shares in Nikola fell 4.6 percent in afternoon trading.
Reuters contributed to this report.
