In recent years as well Indian nuclear scientists have been departing under mysterious circumstances and the rumour is Pak/China/Rus were not facilitating those departures.

“Business deaths” maybe? Biggest economy doesn’t like competition.

https://www.ndtv.com/india-news/11-indian-nuclear-scientists...

https://www.sundayguardianlive.com/investigation/7559-atomic...

https://www.theweek.in/news/india/2021/01/06/from-the-archiv...

https://asiatimes.com/2019/07/indias-vanishing-nuclear-scien...

https://www.unrevealedfiles.com/the-strange-disappearance-of... — this one just turned up in Google. Seems like a blog, not a news org.