The Indian government Thursday vowed to let the law take its course against the crew of Enrica Lexie Napoli, an Italian merchant ship whose security personnel shot dead two Indian fishermen mistakenly as pirates Wednesday off the coast of southern India.

Indian Defense Minister A.K. Anthony said the incident was unfortunate and an investigation is going on while the law would take its course. Indian Home Secretary R. K. Singh said a case has been registered against the crew of the Italian vessel.

The Ministry of External Affairs summoned the Italian Ambassador and lodged a strong protest over the killing of the two fishermen.

Indian External Affairs Ministry's Secretary (West), M. Ganapathi, told Italian envoy Giacomo Sanfelice di Montefort that the captain of the Italian ship has to cooperate with Indian investigators in the case in which security guards fired at the two fishermen after mistaking them for pirates.

"We are working in very close cooperation with the Indian authorities. It is in any case a very sad incident. What I want to underline is that the Italian ship moved voluntarily into the Kochi port," the Italian Ambassador told the media after meeting the Indian official in the national capital.

However, he added: "The Italian Navy followed the international protocol as it was approached by a vessel which did not stop when flash lights were sent."

Local media said the Indian police and coast guard have not been given clearance for the arrest of the crew yet by the foreign ministry, triggering speculation that India is under pressure from the Italian government to release the crew, detained with the vessel at the port city of Kochi.

The two fishermen in a boat were killed after guards on board the Italian merchant vessel fired at them off the Alapuzha coast, 14 nautical miles from the coast Wednesday evening, suspecting them to be pirates.

Though 11 fishermen were on board the vessel, the two were only awake at the time of the incident, while the nine others were asleep.