The explosion took place in the morning at a Unipetrol facility in the town of Kralupy nad Vltavou, north of Prague, the BBC reported.
The cause of the explosion was not yet known.
"We have received information about six dead and several others seriously injured," fire service spokeswoman Vladimira Kerekova told CTK news agency.
In a brief statement, Unipetrol said a fire broke out in a storage tank and that there was no further danger. Czech TV said there was no risk to residents in Kralupy as the town was some distance from the plant.
Unipetrol is one of the largest oil distributing companies and producer of plastics in the Czech Republic.
The plant manufactures toughened polystyrene as well as synthetic rubber.
(This story has not been edited by Social News XYZ staff and is auto-generated from a syndicated feed.)
