THE wife of Indian minister Shashi Tharoor, found dead in a luxury hotel after accusing her husband of being unfaithful, suffered an "unnatural, sudden death", a doctor who performed an autopsy on her body said Saturday.

"More tests" are needed to determine the cause of Sunanda Pushkar's death and the final results will not be known for two to three days, Sudhir Gupta, one of three doctors who performed the autopsy, told reporters.

He added Pushkar's body had "some physical injuries", but it was unclear whether they were related to her death.

After the autopsy Mr Tharoor, dressed in a long white Indian kurta, and other mourners carried his wife's shrouded body on a litter garlanded with marigolds for cremation according to Hindu rites.

Some of Mr Tharoor's cabinet colleagues also attended the cremation.

Mr Tharoor found his wife dead in a luxury hotel room Friday, just two days after she accused him on Twitter and in other media of having an affair with a Pakistani journalist, Mehr Tarar.

"There were no signs of any foul play," his press assistant Abhinav Kumar told reporters. "She seemed to be sleeping in a normal way but later it was found she was dead."

A police probe has been launched into her death.

Earlier Saturday, Mr Tharoor was admitted to the same top government hospital where his wife's autopsy was performed after complaining of "general chest discomfort", a hospital spokeswoman told reporters.

But his test results were normal and he was released. TV footage showed him leaving the hospital looking ashen.

Pushkar, 52, a Dubai-based entrepreneur before marrying Tharoor in 2010, had been taking medications for various illnesses, including tuberculosis, according to local media.

In one of her last tweets, which later appeared to have been removed, she wrote: "Whatever is destined to happen will happen, will go smiling".

Indian social media users called it the first "death by Twitter", with the drama being played out over the micro-blogging site.

The tragedy sent shockwaves through New Delhi's social set. Friends had described Pushkar as the "life of any party".

The couple appeared deeply in love when they wed and were a glamorous pair on the social scene, but the rumour mill had been abuzz for months with talk of marital problems.

Indian newspapers splashed the death on their front pages. "Soon after Twitter war, Sunanda Pushkar found dead in Delhi hotel," said the tabloid Mail Today in a headline.

Events began unfolding late Wednesday when a curious messages appeared on the Twitter account of the suave thrice-married Mr Tharoor, a former high-flying UN diplomat, novelist and key government spokesman.

They showed private exchanges purportedly between the 57-year-old minister (@shashitharoor) and Pakistani journalist Tarar (@mehrtarar), in which she professed her love for him and he said his wife had discovered their relationship.

Mr Tharoor, known as "Mr Twitter" with over two million followers, quickly responded by saying his account was "hacked", but Pushkar spoke to newspapers saying she sent the messages.

She also raked up a corruption scandal related to the Indian Premier League (IPL) cricket tournament that almost wrecked Mr Tharoor's career in 2010 and led him to resign from the cabinet.

Both Pushkar and Mr Tharoor had denied any wrongdoing.

Seeking to draw a line under the Twitter row, Mr Tharoor issued a joint statement Thursday in which he blamed unauthorised tweets and distorted media reports for the "unseemly controversy".

The statement said the couple were "happily married".

Cricket-loving Mr Tharoor and his wife, the mother of an adult son from a former marriage, had been staying at the hotel since Thursday while work was being done to their home.

Television anchor Sagarika Ghose said she spoke to Pushkar on Friday, saying she appeared depressed and was sobbing uncontrollably.

The Pakistani journalist whom Pushkar accused of "stalking" her husband strongly denied having a relationship with the former UN diplomat.

Reacting to Pushkar's death, Ms Tarar tweeted: "I'm absolutely shocked. This is too awful for words. So tragic I don't know what to say. Rest in peace, Sunanda."

Mr Tharoor, a thrice-married father of grown sons, spent three decades in the UN where he was beaten to the post of secretary general by Ban Ki-moon.

The author then quit the UN and entered Indian politics in 2008 as a ruling Congress party MP.

Mr Tharoor's son, Ishaan, a journalist at Time magazine, requested "that everyone please respect our family's privacy".