The former Banaras Hindu University (BHU) Vice Chancellor was on his way to Delhi but complained of severe chest pain at the Lal Bahadur Shastri airport late on Sunday night.
He was rushed to the BHU hospital but could not be saved.
Mr Singh hailed from Jaunpur in Uttar Pradesh and was the founder of the premier Centre for Cellular and Molecular Biology (CCMB) in Hyderabad.
He had won international acclaim for his work on tribals in Andaman and Nicobar. He was the director of the CCMB between 1998 to 2009.
Chief Minister Yogi Adityanath has mourned the demise of Singh and has said that in his passing away, the country has lost an eminent scientist and an illustrious teacher.
In a condolence message issued on Monday, the Chief Minister said that in pursuing studies and excelling despite adverse situations, Lalji Singh reached pinnacle of his stream and has left behind an example for the new generation to emulate.
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