The Indian government was warned in early March about a new, more contagious variant spreading in the country.
That's according to five scientists that took part in a government-organized forum, called the Indian SARS-CoV-2 Genetics Consortium, or INSACOG.
The sources told Reuters exclusively that despite variant warnings, the Indian government failed to impose measures to stop the spread of the virus.
Millions of largely unmasked people attended religious festivals and political rallies and tens of thousands of farmers continued to protest Prime Minister Narendra Modi's agriculture policy.
The world's second-most populous country is now battling a second wave of infections, with more than 300,000 a day for over a week.
It's the worst streak anywhere in the world since the start of the pandemic and scientists say it's accelerated by new variants.
INSACOG was set up as a forum of scientific advisers by the government in late December to detect genomic variants of the coronavirus that might threaten public health.
An INSACOG member told Reuters researchers first detected the Indian variant as early as February and issued official warnings in early March.
Modi's office did not respond to a request for comment.
But some scientists say the surge was much larger than expected and cannot be blamed on political leadership alone.