Nearly a million low-caste Hindus, sporting commemorative scarves and demanding equal rights in the hierarchical society of India, descended on a Bombay park yesterday to mark the 50th anniversary of the death of Bhimrao Ambedkar, the champion of the underclass and an architect of the constitution.

They came from all over the country, riding on trains for as long as three days, to pay homage to the man who campaigned to improve the lot of the Dalits, or Untouchables, the lowest rung on an inescapable caste system and a social group still suffering persecution for an accident of birth.

“We have respect in our souls for him. He remains our god,” said Lakhan Lal, a vegetable seller from Sagar, in Madhya Pradesh. With his wife, Hasina, and 12-year-old son, Azad, he had travelled 36 hours to sit on a piece of dirty black plastic under a makeshift tent in the middle of Shivaji Park, the site of Dr Ambedkar’s cremation in 1956.

He has observed this ritual for the past ten years, but this year was distinctive because of the anniversary. It was also a day marked out for special attention by the authorities during a time of heightened social tension in the state of Maharashtra, whose population is one fifth Dalit.

Violent clashes broke out in Bombay last week after the desecration of a statue of Dr Ambedkar in Kanpur, an industrial city in Uttar Pradesh. Several people were killed when police fired upon mobs who were setting fire to trains, cars and buses. The attacks occurred against a backdrop of unrest after the murder in September of Surekha Bhotmange, 45, her 17-year-old daughter and two sons by fellow villagers over a land dispute. Both women were raped.

The botched handling of the case by police has energised the Dalit movement, reviving fears among the higher castes of a social uprising.

Nearly 1,000 police officers were deployed in and around the park, while the Government drafted in special border security forces and erected towers fitted with closed-circuit television to spot troublemakers.

Schools and colleges were closed. The fears proved unfounded; the day passed off peacefully, in a carnival atmosphere. Divaya, Mirabi, Prembai and Shanti, four women from Madhya Pradesh, were in excitable mood as they queued for free personal accident insurance from a consortium of state insurance companies. Forced to endure regular abuse, they need the 50,000 rupees (£560) cover.

“In the villages, rapes are the norm,” John Dayal, the president of the All India Catholic Union and a Dalit activist, said. “Fifty years after the death of Ambedkar, the situation of the Dalits is only marginally improved. Even the globalised market in India has no place for them.”

Despite a quota of government jobs reserved for the “scheduled castes, tribes and other backward castes”, discrimination prevails, particularly in rural areas. “Casteism has not gone from people’s hearts,” Vivek Thawal, a Dalit bank cashier, said. “Even if you are well qualified and competent, you will not get a job.”

A centuries-old prejudice is slowly easing. Before Dr Ambedkar, a Dalit barrister who became the first law minister in independent India, someone such as Sudam Gobinderao Mask, 32, could not have gone to university and become a life insurance salesman. He has travelled about 500km (300 miles) from the city of Salegaon for the rally. “He [Dr Ambedkar] gave us the right to an education, and for that I come here every year,” he said.

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