Indian police and coastguards are questioning the captain and crew of an Italian cargo ship that fired at an Indian trawler, killing two fishermen.

Reports say the Italians mistook the Indian fishing boat for a pirate vessel on Wednesday evening.

Indian Defence Minister AK Antony has described the killings as "very serious" and an "unfortunate incident".

The Italian ambassador in Delhi was summoned by the foreign ministry on Thursday over the shooting.

Indian officials say they are surprised at the mistake and that the fishermen did nothing to threaten the Italian ship.

Following the shootout, the Indian coast guard sent two boats and an aircraft to intercept the ship.

The Kerala state government has authorised a payment of 500,000 rupees ($10,125; £6,450) each to the dead fishermen's families.

'No weapons'

The Italian ship, identified as the MV Enrica Lexie, fired at the fishermen in waters off India's southern state of Kerala, the Indian navy said in a statement.

Officials said the vessel was bound from Singapore to Egypt, with a crew of 19 Indians.

The Italians say the crew members fired in self-defence - after initially firing warning shots - because they feared their vessel was about to be attacked.

A senior official in Kerala, PG Thomas, said the attack was unwarranted as there were "no weapons on the trawler".

Indian officials said nine of the 11 fishermen in the trawler were asleep and the two victims were steering it when the incident happened.

"The fishermen did not fire at the ship. They couldn't have been mistaken for pirates," said senior Kerala police official P Chandrashekhar.

"The Indian trawler was 100m from the ship. The trawler wanted the ship to pass."

Piracy has emerged as a major threat to merchant ships in the Indian Ocean and the Arabian Sea, with Somali pirates hijacking ships and their crews for ransom.

Pirate attacks have come down recently partly because more armed guards are now deployed on board ships.

Source: BBC News