An Indian pharmacist died and his boss was left hospitalised after the pair drank a chemical concoction they had developed in an effort to treat coronavirus, police said on Saturday.
The men worked for a herbal medicine company and were testing their treatment – a mix of nitric oxide and sodium nitrate – at a home in southern Chennai city.
K Sivanesan, 47, died on the spot, said local police chief Ashok Kumar.
His colleague Rajkumar is recovering from the poisoning.
Kumar said Sivanesan bought the chemicals from a market and developed the formula after conducting internet research.
There are no approved medicines or vaccines for treating COVID-19, triggering a global race for a new drug for the disease that has killed nearly 300,000 people.
India have seen record spikes in coronavirus cases this week, with John Hopkins reporting cases stand at 61,356 and the number of deaths at 2,041.