NEW DELHI: India's Supreme Court convicted a confidante of the late chief minister of Tamil Nadu on Tuesday in a corruption case that will put her behind bars and effectively end her bid to become chief minister of the southern state.

The court found V.K. Sasikala guilty in the disproportionate assets case, upholding a four-year jail term handed down by a lower court and banning her from seeking elected office for 10 years.

The verdict delivered a decisive blow against Sasikala, who had emerged from the shadows after three decades as a low-profile adviser to claim the mantle of five-times Chief Minister Jayalalithaa Jayaram who died in December.

Sasikala mounted a bid to oust Tamil Nadu's caretaker Chief Minister O.P. Paneerselvam, corralling lawmakers from their regional ruling party into a resort hotel in an attempt to stop them from defecting to her opponent's camp.

The power struggle in the state of more than 70 million that has attracted foreign auto makers and consumer electronics firms, comes amid rising social unrest that has raised doubts over its attractiveness as a place to do business.

Known as the "Detroit of Asia", Tamil Nadu is India's second-largest manufacturing state. It hosts auto makers including BMW, Daimler, Hyundai , Ford, Mitsubishi, Nissan and Renault.

Sasikala, who first won the favour of Jayalalithaa by making campaign films and went on to run the household of the actress-turned-politician, was ordered to turn herself in to a court in Bengaluru, capital of the neighbouring state of Karnataka, that convicted both in 2014.

The disproportionate assets case was first filed in 1996 by Subramanian Swamy, a veteran lawyer and politician from Indian Prime Minister Narendra Modi's nationalist ruling party. "After 20 years, I won," Swamy said in a tweet.

Jayalalithaa was jailed in 2014 for holding 530 million rupees ($8 million) in unaccounted cash and property accumulated during her first term in power. She stood down following the verdict only to be freed on bail, and returned to office months later.

Sasikala was also a defendant in the case. She has been ordered to pay a fine of 100 million rupees ($1.5 million) and cannot appeal the verdict.

"She may file a petition for review, but generally it is not entertained in criminal matters," said B.V. Acharya, who had earlier acted as a public prosecutor in the case.

Representatives for Panneerselvam, the acting chief minister, and for Sasikala could not be reached for comment.

Their party's official Twitter handle expressed its support for her, saying that whenever Jayalalithaa had been "in despair" Sasikala had "shared the burden".

"She is doing the same now, truth will prevail," it said.