The Bhopal gas tragedy in 1984 occurred due to the leakage of which highly toxic chemical gas?

The Bhopal gas tragedy, one of the world's worst industrial disasters, occurred on the night of December 2–3, 1984, at the Union Carbide India Limited ($\text{UCIL}$) pesticide plant in Bhopal, Madhya Pradesh, due to the leakage of highly toxic Methyl Isocyanate (${\text{CH}}_3\text{NCO}$) gas.