Two workers were killed and one suffered serious injuries in an accident at a fireworks unit in Venduvarayapuram near Sivakasi on Wednesday. The blast occurred around 5.10pm when Alphonse, 55, and V Muniasamy, 30, from Periyar colony in Tiruthangal and Govinda Babu, 30, from Koomapatti were handling chemicals while making the fireworks. Alphonse and Muniasamy died on the spot, while Babu is undergoing treatment at the Centre of Excellence for Burns Treatment at Sivakasi. Eight rooms in the unit suffered damages and one room where the blast occurred was reduced to rubble. Police said the blast was caused due to friction in the volatile chemical mixture.