A major explosion hit a petrochemical complex in the northeast Japan city of Sendai hours after the biggest earthquake in Japanese history triggered a devastating tsunami, media reports said.
TV images showed huge orange balls of flame rolling up into the night sky as fires raged around the complex.
A huge fire also engulfed a Cosmo oil refinery in Iichihara near Tokyo as the quake brought huge disruption to Japan's key industries.
Sony Corp. suspended production at its six plants in Miyagi Prefecture which was hard hit by the magnitude 8.9 quake and its neighbouring Fukushima Prefecture, it said, adding it has evacuated all employees there.
Nissan said it had suspended operations at four plants, with small fires breaking out at a facility in tsunami-hit Fukushima and Kawachi County that had since been extinguished. It said two employees had suffered injuries.