The fire erupted at a laboratory of a Waste Management Factory in Katunayake Free Trade Zone (FTZ) has been doused, police said.
They said the fire was reported at around 4.45 this morning.
Meanwhile, a Colombo Fire Brigade official said four firefighting trucks were deployed to put out the fire together with the Army and Navy personnel.
The fire had caused extensive damage to the laboratory, police and the Fire Brigade officials said.
The cause of the fire and the damage caused is yet to be estimated, the police said and no injuries or deaths reported. (Chaturanga Samarawickrama)