Repairing the damage in Annukur's Dalit colony

"The parents of children that go to the same school as hers did this," she says. "They hate us, and they may come again."

They are rebuilding the Dalit colony of Annukur village, rethatching the roofs that went up in flames one violent night earlier this year.

But the deep divisions caused by the clash remain and fester.

Dalit politics is acquiring a new urgency in Tamil Nadu, as the lower castes realise that they no longer have to tolerate abuse and discrimination.

Thiru Mavalavam of the Dalit Panthers party says political awareness has been a long time coming:

Caste-based jobs remain, but Dalits are chipping away at political exclusion

"Our women have been molested, our houses burnt down. For 30 years we have endured atrocities. We have two ways to fight this - militancy or politics. We choose politics. We're fighting for our rights under the Dalit banner."

It takes just five minutes for the children to walk from school to their homes in Annukur's Dalit colony. But they cross a cultural divide as wide as any ocean.

Caste champion

All over rural India, Dalits live separately from other Hindu castes. Despite years of reform, of laws banning untouchability and the steady march of education and development, Dalits still suffer.

Further north in Bihar - India's most caste-ridden state - the country's most successful Dalit politician is on the campaign trail.

Ram Vilas Paswan has been a cabinet minister; he is an unabashed caste champion and his majority at the last election was more than 500,000 votes.

"Untouchable" former minister: Ram Vilas Paswan

This time around, Mr Paswan is linked up with the BJP, a traditional protector of India's higher castes.

At the political level, if not in real life, the times are definitely changing.

"Because I come from the Dalit family, which have been untouchable - this has helped me," he says. "I can recognise the feeling of the downtrodden and the poor section of society."

In the Dalit villages of India, the traditional jobs - basket weaving, raising pigs and helping cremate the dead - are still the tasks of the lower castes.

But education and growing awareness means that Dalit concerns have to be taken seriously. They are not politically untouchable anymore.