An explosion and fire at a petrochemical plant in Russia’s republic of Tatarstan killed at least two workers and injured dozens more, the facility’s owner said Tuesday, according to the Moscow Times.

The blast occurred at Nizhnekamskneftekhim, Russia’s largest producer of synthetic rubber and plastics, located in the industrial city of Nizhnekamsk, around 170 kilometers (105 miles) east of Kazan.

Sibur, the petrochemical company that owns the plant, said the explosion was likely caused byan “equipment malfunction.”

It said injured workers were receiving medical care and that the facility had been evacuated.

Tatarstan’s prosecutor’s office said it had launched a preliminary investigation and could pursue criminal charges if safety violations are found.