AP Abdullakutty, who represents Kannur in the state legislature, has been accused of sexually assaulting a woman in a hotel in Thiruvananthapuram.
She has also alleged that the politician, who is 46, threatened her against disclosing what had happened.
The Congress leader has denied the charges. "I have several things to reveal myself. I will do it at the right time. These are attempts made to defame me and the party for no reason," he said.
A personal aide of Chief Minister Oommen Chandy was arrested in connection with the scam.
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