Official sources indicated that the searches were held following 'some inputs', but they did not elaborate.
Income Tax officials were also 'assisting', the local poll officials, they told PTI. The outcome of the searches were not known immediately.
Following information about the searches, a large number of Dravida Munnetra Kazhagam workers gathered in front of Kanimozhi's house expressing solidarity.
DMK president M K Stalin in a statement at Chennai said the raids were an outcome of 'fear of a damning defeat', for Bharatiya Janata Party's candidate Tamilisai Soundararajan in Tuticorin.
She is also the BJP's State unit president.
"This is murder of democracy," Stalin said and alleged that Prime Minister Narendra Modi has buried the autonomous feature of the Election Commission through such actions.
The DMK chief said his party would work towards ushering in reforms in the appointments of Chief Election Commissioner, Election Commissioners and State Chief Electoral Officer.
"If needed, we will not hesitate to approach the Supreme Court," he said.
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