Mallapur (Karnataka), Nov 30 : Investigating agencies are finding it tough to probe the alleged leak at the Kaiga nuclear plant here, as no CCTV cameras were placed near the water cooler, the place where the leak took place.

The radiation leak has left 55 employees in the maintenance unit of the plant with suspected radiation poisoning.

They are being treated for increased level of tritium, a radioactive isotope of hydrogen in their bodies, after they drank water from the cooler located in the operations area on Tuesday.

Tritium, also known as Hydrogen-3, is used in research, fusion reactors and neutron generators. Atomic Energy Commission Chairman Anil Kakodkar had on Sunday said the leakage at the Kaiga nuclear plant appears to have been a malevolent act of a disgruntled employee.

Union Minister of State for Science and Technology Prithviraj Singh Chavan also said it was an act committed by a disgruntled employee.

Investigating officers are now working with the footage gathered of nearby areas. They have also narrowed the probe down to 10-15 suspects.

Dr S K Jain, CMD, Nuclear Power Corp has said it will not be tough to find the suspect, as the authorities have a list of all those having access to the water cooler.

B Bhattacharjee, a member of the National Disaster Management Authority (NDMA) said, "It seems some mischief person inserted some titrated water and contaminated the whole cooler."

Intelligence bureau officials will examine finger prints found on the cooler and match it with the data available in the plant''s biometric security system. (ANI)