The two Italian marines are charged with killing the two fishermen off India's coast on February 15, 2012.

One of the two Italian marines accused of murdering fishermen off the coast of Kerala almost four years ago will not be returning to India to face trial after being allowed home temporarily for medical treatment, an Italian senator has announced, setting the stage for a likely diplomatic flare-up.The Supreme Court had granted Massimiliano Latorre, who suffered a stroke while in New Delhi in 2014, a period of leave in Italy for medical treatment, but he was supposed to return by Friday. The second sailor on trial, Salvatore Girone, is being held in the Italian embassy in New Delhi. Massimiliano Latorre will not return to India , and furthermore, the possibility of asking for Salvatore Girone's return is being explored," said Nicola Latorre, president of the Senate Defence Committee, according to Italian media.Kerala Chief Minister Oomen Chandy has said Prime Minister Narendra Modi must intervene."The Italian government has stood up for its soldiers, our government must stand up for us," said T Peter, a top official with the National Federation of Fishermen.The pair of marines has said in court that they accidentally killed two Kerala fishermen when they mistook a fishing boat for a pirate ship and fired warning shots while protecting an Italian oil tanker in 2012.Italy and India have been at loggerheads over who has jurisdiction over the case, and Italy has sought international arbitration.In 2013, Italy reversed an initial decision not to send the marines back to India to stand trial after a home visit, in a bid to tone down the diplomatic row.