New Delhi: Italian deputy Foreign Minister Staffan de Mistura on Wednesday expressed ‘terrible sadness’ over the killing of two Indian fishermen but insisted their death took place in international waters.

"We do acknowledge and recognize that two Indian fishermen died. No one doubts it, and it is terribly sad," the minister said after talking with Indian officials here over the arrest of two Italian naval guards on board an Italian ship who fired at the fishermen thinking they were pirates.

But he said the February 15 incident took place in international waters off Kerala and investigation will ascertain the exact position of the Italian ship which carried the naval guards.

“We are taking it seriously. We are definitely expressing terrible sadness and regret over the loss of lives. Two Indian fishermen did die and they belonged to poor families of Kerala," he added.

We will go by Indian law: Perneet Kaur

India will go by its law while dealing with the arrest of two Italian Marines over the killing of two Indian fishermen, minister of state for external affairs Preneet Kaur said on Wednesday.

"We will certainly go by our law," the minister told reporters after meeting Italian deputy foreign minister Staffan de Mistura. She said the minister expressed "regret and sorrow" over the Feb 15 killings of the two fishermen off Kerala that has led to a diplomatic row between India and Italy.

"As far as the law point is (concerned), they have their interpretation and we have our interpretation," she said. Italy insists the incident took place in international waters and that the Marines cannot be tried in Indian courts. New Delhi contests both the claims.

Kaur said the Italian Marines "are on Indian soil" and "we have taken note of what (de Mistura) said.