The Karnataka police has filed a first information report into the case of radiation contamination of a drinking water cooler at the nuclear power plant here, but the document does not name any accused.
"We have filed the FIR last night," said Superintendent of Police of Uttara Kannada district, of which Kaiga is a part, Raman Gupta.
He said the FIR has not named anybody and is general in nature based on the complaint filed by Kaiga plant authorities.
Police sources said all angles of the case, including probability of theft of tritium, which carries an astronomical price tag, is being investigated.
The investigation is being done by the Intelligence Bureau and some officials of the Nuclear Power Corporation of India in coordination with the state police.
The NPCIL owns and operates the Kaiga plant.
The state police joined the investigation late, as Kaiga authorities initially did not file a complaint.
"We have joined the investigation now. There is no clue as of now," Gupta said. "All angles are being investigated".
On reports of sleuths looking at the angle of possible role of Bangladeshi workers at the plant, he said, like any other part of India, there could be some of them who had come to the country several years ago and procured domicile documents.
"They (Bangladeshi workers who came to India several years and obtained Indian domicile documents) might be there (at Kaiga like any other part of India)," Gupta said.
Kaiga generation station has four units of Pressurised Reactors each of 220 MW(e) at Kaiga. Units 2 and 3 are operating normally. Unit 4 is under commissioning while Unit 1 is under annual maintenance shutdown since October 20 this year.
On November 24, some routine urine samples in workers indicated higher content of tritium than normal and the source of contamination was identified to be a drinking water cooler.
Except two of the workers, all who had consumed contaminated water, have resumed their duties in the non-radiation area of the plant, NPCIL said.
"In the case of two persons who had high tritium in their body, further medical management is being carried out to bring down their potential radiation exposure to less than that prescribed by the Atomic Energy Regulatory Board in a short time," NPCIL chairman and managing director SK Jain had said.
Authorities believe that some "mischief maker" added a small quantity of tritiated heavy water to the cooler, possibly from a heavy water sampling vial, through its overflow tube.Employees who had access to tritium and those in the operating area where the water cooler was kept have already been questioned by the investigators, the police said.