A self-styled Gandhian anti-corruption campaigner has left prison and promised to carry on his fast in the capital after India's beleaguered government caved in to huge protests across the country.
After three days in jail, the government has allowed Anna Hazare to stage a 15-day hunger strike.
Mr Hazare, who had been arrested earlier in the week, had refused to leave jail until he was allowed to fast publicly.
Outside the jail, hundreds of Mr Hazare's supporters waved India's national flag and danced to Bollywood music as they awaited his appearance. One group offered prayers to the Hindu gods, others chanted 'the whole country is Anna'.
He will later take a car to open grounds in central Delhi, where supporters were making final preparations for his fast.
A fumbling official response has seen the Congress party-led government face one of the most serious protest movements since the 1970s, just the latest setback for Prime Minister Manmohan Singh's second term.
A medical team was on standby to monitor Mr Hazare's health as he began his hunger strike in jail and a sharp deterioration could further worsen the crisis for the government.
A weak political opposition means that the government should still survive the crisis, but it could further dim the prospect for economic reforms and hurt the Congress party in key state polls in 2012 that will pave the way for a general election in 2014.
The protests across cities in India have rocked the ruling Congress party and sent shockwaves through the political class.
In the financial capital, Mumbai, the city's iconic lunch carriers, known as Dabbawallas, were set to go on strike in sympathy with Hazare.
One Facebook fan page for Mr Hazare has 285,000 followers, while the India Against Corruption page on Facebook has more than 350,000 followers where links and messages of support are posted.
Several Twitter accounts have been set up by supporters to send out messages of where and when to protest.
Mr Singh, 78, who is widely criticised as out of touch, dismissed the fast by Mr Hazare as 'totally misconceived' and undermining the parliamentary democracy.
Mr Hazare, a long-time social activist who is often compared to independence leader Mahatma Gandhi, became the unlikely thorn in the side of the ruling coalition when he went on hunger strike in April.
He called off that fast after the government promised to introduce a bill creating an anti-corruption ombudsman.
The so-called Lokpal legislation was presented in early August, but activists slammed the draft version as toothless because the prime minister and judges were exempt from probes.
