The persons held belonged to a non-Dalit caste and were residents of a colony at Avaniapuram, the Madurai suburb where the incident took place, police said.

Provoked by news of damage to Ambedkar's statue, a group of Dalit students belonging to a State-run hostel in the city, blocked traffic and stoned about a dozen buses on Arterial Anna road here last night and resorted to a road block this morning, too.

However, the police, who had persuaded them to return to their hostel last night, rounded up the protesters this morning and later released them, police said.

At Tindivanam, protesters damaged several State transport buses and private shops last night, leading to the police firing a few shots in the air to disperse them.

A police officialsaid the authorities did not arrest any of them as they did not want the situation to worsen. The agitators were in a volatile mood, he added.

Meanwhile, the Tindivanam district administration held an all-party meeting to defuse the tension.

TNCC president Tindivanam K Ramamurthy and Puthiya Tamizhagam founder K Krishnasamy condemned the damage caused to Ambedkar's bust-sized statue and the violence that followed the incident.

In a statement here, Ramamurthy said the police should take impartial action against those who had vented their casteist anger on Ambedkar's bust. The violent protests at Tindivanam which lead to the police firing in the air was a sign of the worsening law and order situation in the State, he said.

Recalling that a commission of inquiry had been appointed to probe a similar incident -- when an Ambedkar statue was found with a garland of slippers at Tindivanam during the 1998 elections -- Ramamurthy said the probe panel's report was not made public and the culprits wentscot-free.