An OpenAI researcher-turned-whistleblower has been found dead in an apartment in San Francisco, authorities said.

The body of Suchir Balaji, 26, was discovered on 26 November after police said they received a call asking officers to check on his wellbeing.

The San Francisco medical examiner’s office determined his death to be suicide and police found no evidence of foul play.

In recent months Mr Balaji had publicly spoken out against artificial intelligence company OpenAI’s practices, which has been fighting a number of lawsuits relating to its data-gathering practices.

In October, the New York Times published an interview with Mr Balaji in which he alleged that OpenAI had violated US copyright law while developing its popular ChatGPT online chatbot.

The article said that after working at the company for four years as a researcher, Mr Balaji had come to the conclusion that “OpenAI’s use of copyrighted data to build ChatGPT violated the law and that technologies like ChatGPT were damaging the internet”.

OpenAI says its models are “trained on publicly available data”.

Mr Balaji left the company in August, telling the New York Times he had since been working on personal projects.

He grew up in Cupertino, California, before going to study computer science at the University of California, Berkeley.

A spokesperson for OpenAI said in a statement cited by CNBC News that it was “devastated to learn of this incredibly sad news today and our hearts go out to Suchir’s loved ones during this difficult time”.

US and Canadian news publishers, including the New York Times, and a group of best-selling writers, including John Grisham, have filed lawsuits claiming the company was illegally using news articles to train its software.

OpenAI told the BBC in November its software is “grounded in fair use and related international copyright principles that are fair for creators and support innovation”.