NEW DELHI — India said on Tuesday that it had intercepted a Pakistani boat in waters off its west coast with what appeared to be nearly $100 million worth of heroin aboard.

Eight Pakistanis aboard the boat were taken to Porbandar, a coastal town in the state of Gujarat, for further investigation, according to a statement from the Indian Coast Guard. Satellite phones and GPS devices were confiscated, the Coast Guard said.

An Indian Navy official told reporters that the seized cache weighed about 500 pounds in a news conference in Porbandar on Tuesday afternoon. The navy also presented the eight Pakistanis in handcuffs to reporters during the news conference. Pakistan did not immediately issue a statement.

The waters in the Arabian Sea off Gujarat are closely watched by India’s Coast Guard and navy for potential infiltrators from Pakistan.