Nearly 10,000 paramilitary troops moved into town Saturday after police said an Islamic separatist group threatened to blow up a Hindu temple at the site of a demolished 16th century mosque.

Security was tightened as thousands of Hindus began arriving in Ayodhya to hold a Sunday prayer ceremony close to the ruins of the Babri mosque razed by Hindu nationalists eight years ago. That demolition triggered riots killing 2,000 people.

Intelligence reports say a Pakistan-based militant group, Jaish-e-Mohammed, planed to attack the temple, where Hindus keep idols of their gods and goddesses, a police officer said on condition of anonymity.

The Pakistan-based group has not made a public statement about such plans.

Thousands of Hindus will participate in Sunday's ceremony, concluding 108 days of worshipping fire as an expression of resolve to build a temple for their deity, Rama, at the disputed site.

Many Hindus believe Rama, the supreme Hindu god, was born at the site and the mosque was built after the desecration of a temple. Ayodhya is 345 miles east of New Delhi.

"Each devotee coming to Ayodhya for the ceremony will be physically checked and will have to pass through metal detectors," J.S. Deepak, a top district administrator, said.

"The threat perception is too high keeping in mind the large congregation of devotees and a disturbed border situation," he said, referring to tensions building up on the India-Pakistan border over Pakistan's alleged support for militants crossing the border into India to launch attacks.

The temple campaign was blamed for triggering another round of religious violence in February that killed nearly 1,000 people in the western state of Gujarat.