The Coast Guard said they followed standard operating procedure (SOP) while intercepting the hostile boat, which as intelligence inputs suggested, had set sail from the port city of Karachi from Pakistan for some "illicit transaction".
The maritime law enforcement agency reiterated that the vessel was set on fire by its crew members, causing it to explode and later sink. The incident took place about 365 km off the coast of Gujarat's Porbandar in the Arabian Sea on the intervening night of December 31 and January 1 after a hot pursuit by the Coast Guard.
"We saw four men on the boat, they were nowhere looking like fishermen, they wore T-shirts and half pants, and this raised suspicion on our side," Coast Guard Commander (North-West Region) Kuldip Singh Sheoran told reporters.
A search operation is on for the bodies of the crew members and wreckage of the vessel, he said.
"Multiple Indian intelligence agencies are jointly investigating the incident and they will go to the bottom of it," he said on being asked if the occupants of the boat were terrorists.
"We received intelligence input at around 8.30 in the morning (of Dec 31) about the suspicious boat. We dispatched our Dornier aircraft and ship in that direction and by 1 in the afternoon, we had positively identified the ship," he said.
"After the hot pursuit, we fired warning shots, but the boat did not stop. We fired more warning shots. After some time, the crew of the boat set it on fire and later it sank with them (occupants)," the Coast Guard officer said.
He added they had no information on reports that that there were two other suspicious boats in the high seas.
The Coast Guard Commander said they have increased vigilance along the Gujarat coast after the incident and also in view of two upcoming high-profile events in the state - Pravasi Bharatiya Divas and Vibrant Gujarat Summit.
"We are alert round-the-clock, but due to these events, we are on extra alert. Our ships and aircraft are doing their job of patrolling the sea," he added.
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