The survivors of world's worst industrial disaster, the Bhopal gas tragedy have begun an indefinite sit-in in the Indian capital New Delhi to press their demand for a national commission that will look after their long term medical care and rehabilitation. On December 2, 1984, hundreds of tons of a toxic gas leaked from a pesticide plant owned by the Union Carbide, killing nearly 8000 people. Thousands more sustained severe afflictions. Twenty three years on, the survivors continue their battle for proper medical care and aid. FSRN's Bismillah Geelani reports from New Delhi.