Jayalalithaa Jayaram, the chief minister of the South Indian state of Tamil Nadu, was sentenced to four years in jail on Saturday in a high-profile corruption case that has lasted nearly two decades.

The verdict against the former movie star, who is one of the most popular politicians in south India, delighted some supporters of rival parties who were beaten in the general election held earlier this year.

A special court in Karnataka found Jayalalithaa guilty of "disproportionately" amassing about Rs530 million ($8.7 million) outside her known sources of income, prosecution lawyers told reporters late in the evening.

"She has been taken into custody ... Medical check-ups will be done, thereafter she'll be sent to jail," one of the prosecution lawyers said. Three of Jayalalithaa's aides were also sent to jail.

The court has also fined the four-time chief minister Rs1 billion ($16 million), which will be taken from the properties that have already been seized by the court.

Jayalalithaa is legally obliged to now step down as the head of Tamil Nadu, which she has governed since 2011 under her latest term. However, she will have the option of approaching a higher court which could overturn the verdict.

Television reports showed supporters of Jayalalithaa, the chief of the AIADMK party, clashing with police in Bangalore and Chennai. Workers of rival Tamil party, DMK, burst crackers in celebration.

The portly, fair-skinned Jayalalithaa acted in several movies before joining politics and has a huge fan following. She endeared herself to millions by distributing free laptops, grinders and fans to voters.

"I am pleased that the Indian democratic system is working," Subramanian Swamy, a petitioner in the case and a leader of Prime Minister Narendra Modi's Bharatiya Janata Party (BJP), told the television channel Times Now. "It is an appropriate punishment."

Swamy said that the verdict could weaken AIADMK and present his party with an opportunity to build its base in the state, where it has had little success so far.

Experts say Indian courts have historically been lenient on powerful politicians, with many former state and federal chief ministers out on bail despite facing serious charges.-Reuters