NEW DELHI, 18 July — India’s opposition parties yesterday came down heavily against the government for a new anti-terror law enacted in March, which has been invoked to arrest key ruling coalition MP Vaiko Gopalasamy.

Except Sonia Gandhi’s Congress party and Tamil Nadu’s ruling AIADMK party, top opposition parties joined in a discussion in the Lok Sabha and said the Prevention of Terrorism Act (POTA) was open to political misuse.

Vaiko, whose four-MP MDMK party is a member of Prime Minister Atal Behari Vajpayee’s coalition, was arrested on Friday in Tamil Nadu capital Madras for his support to the Tamil Tiger guerrillas in neighboring Sri Lanka.

AIADMK leader and Tamil Nadu Chief Minister Jayaram Jayalalitha earlier wrote to Deputy Prime Minister L.K. Advani making a case for the arrest of Vaiko. Yesterday, opposition leaders raised the issue in the house immediately after question hour ended.

“POTA is a law of the jungle,” said Communist Party of India-Marxist (CPM) MP Somnath Chatterjee. “Vaiko’s case proves it can be misused politically.

Somnath also said that if the arrest of Vaiko and eight other MDMK leaders was justified, then the two MDMK ministers in Vajpayee’s government should quit.

The eight MDMK leaders were arrested last week for publicly supporting the Liberation Tigers of Tamil Eelam (LTTE), which is outlawed in India for assassinating former Prime Minister Rajiv Gandhi.

Samajwadi Party leader Mulayam Singh Yadav echoed the observations and warned Jayalalitha against invoking the law to book political adversaries.

But Congress MP Mani Shankar Aiyar criticized Vaiko for acting in an “utterly irresponsible manner” by supporting the LTTE.

Vajpayee’s Hindu extremist Bharatiya Janata Party, which had aggressively pushed POTA despite spirited resistance from opposition parties that dubbed it as draconian, has favored amendments to the law to prevent its political misuse.