The boy was smothered to death, said a senior doctor here on Tuesday citing the postmortem report of the four-year-old who was allegedly killed by his mother at a service apartment in Goa.

Suchana Seth, the chief executive officer (CEO) of an artificial intelligence start-up, was apprehended in Chitradurga in Karnataka on Monday night while she was on her way from Goa to Bengaluru, and the boy's body was found in a suitcase. She was arrested on the directions of the Goa Police.

"He (the child) was strangled to death or what we call smothering. Either a cloth or a pillow was used. The child died due to strangulation. It doesn't look like the child was strangulated using hands. It looks like a pillow or some other material was used. The Rigor mortis had resolved in the child," Hiriyur Taluk Hospital's administrative officer Dr Kumar Naik told reporters.

"Usually in India, rigor mortis resolves after 36 hours but in this child's case, there was no Rigor mortis. So, it has been more than 36 hours since his death," he said. Naik said there was no blood loss or struggle marks on the body.

"We cannot say the exact time but it has been 36 hours since his death," Naik said.

Seth is the CEO of 'The Mindful AI Lab', and according to her LinkedIn profile, she is an AI ethics expert and data scientist with over 12 years of experience in mentoring data science teams, and scaling machine learning solutions at startups and industry research labs.

"She is on the 100 Brilliant Women in AI Ethics List. She has been a Mozilla Fellow at Data & Society, a Fellow at the Berkman Klein Centre at Harvard University, and a research fellow at the Raman Research Institute. She also holds patents in natural language processing," the profile read. Seth is an expert in 'AI Ethics Advisory & Audits' and 'Responsible AI Strategy'.

A postgraduate from the University of Calcutta, and a research fellow from Raman Research Institute (RRI) and spent two years at the Berkman Klein Center for Internet & Society at Harvard University.