Mahdhani shot to limelight through the fiery speeches he made in the aftermath of the Babri Masjid demolition. Born in Mainagapally in Kollam district, a young Mahdhani had already established himself as a prolific speaker at school and in college. Later, he made his mark through speeches delivered in mosques.

In 1991, Mahdhani launched the Islamic Sewak Sangh (ISS) to counter the RSS, an organisation he used to attack through his speeches. In 1992, the Union government banned the ISS following which he was arrested.
In August 1992, he escaped a murder attempt in Kollam allegedly at the hands of the RSS though he lost one of his legs in the bomb blast. The very next year, he launched the People’s Democratic Party  mostly supported by youths.

His speeches were nevertheless found communally sensitive and the  police seized several hundred cassettes of his speeches.

It was one such speech made in Kozhikode in 1992 that led to his arrest in April 1998. He was handed over to the Tamil Nadu police based on the statements made by two of the accused in the Coimbatore blasts case.
The then CM E K Nayanar claimed that the  police had unearthed key evidence proving his involvement in the serial blasts.