JOYSAGAR, July 13: A devastating fire broke out in one of the ONGC rigs under Dimual oil field of Bokota area of Sivasagar district on Thursday night. The incident took place in Bokota Chandbad Rig and the incident created sensation all around. Fire tenders of the ONGC as well as State Fire Service reached the spot and brought the fire under control. No causality has been reported so far. The cause of fire is presently under investigation as per sources.