As tension simmered over the Mullaperiyar dam issue, security was stepped up on the borders here when hundreds of villagers from Tamil Nadu marched towards Kerala protesting alleged attacks on Tamils.

Additional reinforcements were rushed to Lower Camp, a village in Tamil Nadu's Theni district, and adjacent Kumily in Kerala when over 4,000 people took out the protest march. Authorities on both sides of the border prevented any untoward incident though they were apparently caught unaware by the unannounced march of residents from 20 villages in and around Cumbum, who started converging since the wee hours at Lower Camp, 48km from Theni.

Launching a media blitz, Chief Minister Jayalalithaa sought to reach out to the people of Kerala who are up in arms against the neighbour demanding a new dam in place of the 116- year-old Mullaperiyar reservoir citing safety concerns.

In full-page advertisements in mainstream newspapers, she said there is no valid reason to believe that the reservoir is unsafe and people should see through the ‘machinations’ of vested interests and divisive forces in both states.

Jayalalithaa, who had earlier written to her Kerala counterpart Oommen Chandy to reassure him that the dam was totally safe, said: "It is unfortunate that a fear psychosis among the people of Kerala is being built up."

Jayalalithaa's initiative evoked sharp reactions from Kerala ministers and politicians though her counterpart Oommen Chandy sought to play it down, saying: "I only see it as freedom of expression by her."

Defence Minister and senior Congress leader A. K. Antony, who hails from Kerala, said in Kozhikode that Prime Minister Manmohan Singh has assured him that efforts would be taken to arrive at a peaceful solution to the row.

Hitting out at Jayalalithaa, Kerala Minister K. M. Mani asserted that the state does not require permission of Tamil Nadu for building a new dam. "It does not require anybody's generosity and there is no question of backing out under pressure from anybody."

KPCC president Ramesh Chennithala termed as unfortunate Jayalalithaa's remarks that Kerala wanted to help land mafia and commercial interest to set up tourism project.

"It is rather unfortunate and totally baseless," he said in a statement in Thiruvananthapuram.

Meanwhile, a tremor measuring two on the Richter scale was registered this afternoon in parts of Idukki district, where the Mullaperiyear dam is located. Kerala State Electricity Board sources said the data from their seismograph installed at Vazhathoppu near Idukki dam recorded the tremor, the latest in the 24 mild temblors reported in the region since January.

In Theni district, citing alleged incidents of attacks on plantation estate workers from Tamil Nadu in Kumily belt in the past few weeks, the villagers demanded proper protection.

"If the Kerala state is not able to protect them, we will protect them" they told district officials.

A report from Kumily said tension prevailed in the town also where Kerala police stepped up security and blocked the road leading to Tamil Nadu. Additional forces were deployed in the town and shops remained closed while the check-post at the main entry point closed to stop vehicles from either side.

According to Idukki SP George Varghese, Kerala authorities were in touch with their counterparts in Theni district and taken all steps to prevent any violence. The situation was under control in the area where prohibitory orders have already been in place since early this week after some untoward incidents.