The other three sisters and their father, who also jumped into the sea at Kalapet on the Puducherry-Markanam route, were rescued by local fishermen and are undergoing treatment at the Government General Hospital, police said.
While the sisters were staying in the residential quarters of the Aurobindo Ashram for the past several years, their parents were staying in the town limits.
Kottakuppam Sub-Inspector M S Subbiah gave the names of the deceased as Shanthidevi, 70, daughters Arunashri, 50. and Rajashree, 45. The bodies were found washed ashore in coastal villages of Thandrayanpet and Chinna Mudaliarchavady in neighbouring Tamil Nadu by local fishermen who informed police.
The four rescued persons were identified as the father Gadadhar Prasad, 80, and three other daughters Jayashree, 54, Niveditta, 42, and Hemalatha, 40.
The dispute between the sisters and the Ashram Trust can be traced to 2002 when the ashram took disciplinary action against Hemalata Prasad for misconduct after an inquiry by a retired district judge appointed by the Madras high court.
The Supreme Court on December 9 directed them to vacate the ashram within a week failing which police should evict them.
The five sisters staged a high drama on Wednesday with one of the climbing up to the top floor declaring that they would all commit suicide if the police evicted them. However, police held talks and managed to shift them before evicting them later in the evening.
Along with their parents they allegedly struck a suicide pact and proceeded early on Thursday to the Kalapet coastal village to execute their plan, police said.
Meanwhile, the police have stepped up security at the ashram after some activists of Thanthai Periyar Dravida Kazhagam allegedly threw stones at it, damaging some glass panes. Stones were also thrown at other buildings owned by the ashram.
Police said about 50 workers of the Kazhagam were arrested in connection with the incidents. The workers also protested and shouted slogans demanding a probe into the alleged suicide.
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