Police beefed up security around controversial Kudankulam Nuclear Power Plant (KNPP) after a Kerala-based outfit threatened that it would picket the plant.

The Indo-Russian joint venture (JV) nuclear project has been suffering severe protests by anti-nuclear activists, who have repeatedly been raising concerns over safety of nearby residents and environment.

The nuclear plant's first 1000MW reactor, which had gone critical in July this year, is expected to start generating electricity as soon as next month.

The Nuclear Power Corporation of India Ltd (NPCIL), the first reactor of the plant has already achieved 99.76 per cent physical progress, and its commercial operation is expected to start before the end of November this year.

The nuclear JV project in the Tirunelveli district of the state will have two reactors installed by Russia, each with a capacity of 1,000 MW. The second reactor, which has achieved progress of around 96 per cent as of September, will likely start generating electricity in June 2014.

KNPP, which will cost estimated amount of more than Rs 17,000 crore, is going to be India's first pressurized water reactor under the light water reactor category.