Bangalore, Sep 27 (IANS) Tamil Nadu Chief Minister J. Jayalalithaa was late Saturday sent to the Bangalore Central Jail after being sentenced to four years in prison and fined Rs.100 crore for corruption, dealing a huge blow to the charismatic former actor who had dreams of becoming the prime minister ahead of this year's Lok Sabha election.

The 66-year-old stands disqualified as a member of the Tamil Nadu legislature and can't contest elections for a decade -- decisions that are bound to impact both the state and national politics.

Pronouncing his verdict on a legal battle that began in 1996, judge John Michael Cunha held Jayalalithaa and three others guilty of amassing wealth disproportionate to known sources of income.

The other three are V.K. Sasikala, a long-time associate, now disowned foster son V.N. Sudhakaran and J. Illavarasi, a former aide. All three were also sentenced to four years in prison and fined Rs.10 crore each.

The convictions came under the Prevention of Corruption Act and the Indian Penal Code.

As news of the conviction became known, Jayalalithaa supporters who had massed here in large numbers clashed with police near the prison and were taken into custody. The reaction was more violent in Tamil Nadu, where AIADMK activists took to the streets, forcing shops and businesses to shut and stoning buses in most major towns and cities.

Long distance and inter-state bus services in Tamil Nadu were cancelled.

Frenzied supporters also made a bonfire of pictures of DMK leader M. Karunanidhi whose party filed the case against Jayalalithaa in 1996 accusing her of amassing illegally earned wealth. The case took several twists with the special court moving from Chennai to Bangalore.

After the sentencing, a downcast Jayalalithaa sought special medical treatment citing her age and diabetic condition. "The court considered the plea and directed the jail superintendent to ensure medical treatment," said special public prosecutor Bhavani Singh.

"The prosecution proved that the main accused (Jayalalithaa) had amassed disproportionate assets, which were valued at Rs.53 crore when she was the chief minister. We have done our job and the law has taken its course," he told the media.

Singh said the fine can be recovered from the properties seized from her residence and lands she acquired as chief minister in 1991-96.

"Considering the long time (18 years) the case has taken for trial and conviction, and keeping in view the inflationary hike, the court has decided to impose the fine which can be recovered from the sale of assets under its custody."

Saturday's development will leave the AIADMK rudderless in Tamil Nadu, where Jayalalithaa led it to a sweeping win in the Lok Sabha, bagging 37 of the state's 39 seats in May. As of today, she won't be able to return to office in the next two assembly elections -- in 2016 and 2021.

Prime Minister Narendra Modi's Bharatiya Janata Party (BJP) reacted cautiously, saying Jayalalithaa was entitled to pursue legal methods.

Before this year's general election, Jayalalithaa didn't hide her prime ministerial ambitions. And although she did not ally with the BJP, she has enjoyed a close relationship with Modi for years.

Amid attacks on DMK offices and leaders by AIADMK supporters, Karunanidhi frantically appealed to President Pranab Mukherjee, Modi and Home Minister Rajnath Singh to restore law and order in the state.

Bhavani Singh said a bail application cannot be moved if the jail term exceeds three years.

"As Jayalalithaa has been convicted and sentenced, she automatically loses her membership in the Tamil Nadu assembly and thus has to step down from the chief minister's post," government counsel B.T. Venkatesh told IANS.

Jayalalithaa can, however, move the high court in Karnataka or Tamil Nadu seeking suspension of the sentence.

In 2001, when Jayalalithaa stepped down as chief minister after being convicted in a criminal case, she named O. Panneerselvam, a minister, as her successor. A similar situation has now arisen.

She again became the chief minister in 2002 after being acquitted by the Madras High Court.

During her first tenure (1991-96) as chief minister, Jayalalithaa drew Re.1 as salary. The charge against her was that her assets rose from about Rs.3 crore in 1991 to around Rs.66 crore in just five years.

A close aide of AIADMK founder-leader MGR, Jayalalithaa became the party's propaganda secretary in the early 1980s. In 1984, she entered the Rajya Sabha.

She was elected to the Tamil Nadu assembly in 1989.

Two years later, she became the chief minister, sweeping the election held after the 1991 assassination of former prime minister Rajiv Gandhi.

Her party was voted out in 1996 amid corruption charges but she returned to power in 2001.

Jayalalithaa again led the AIADMK to a thumping victory in 2011. This time, she announced a string of populist measures that have proved to be hugely popular in Tamil Nadu.