NEW DELHI (AP) -- India said Tuesday that an Italian decision not to return two marines accused of killing a pair of Indian fishermen last year was unacceptable.
The government allowed the marines to return to Italy in February to vote in national elections and to celebrate Easter with their families. Italy announced Monday it would not send the marines back to India to face trial as had been expected.
The case that has caused a huge uproar in India and angry politicians have attacked the government for allowing the two Italians to leave the country. Opposition lawmakers protested in both houses of India's Parliament demanding the government explain what it plans to do to bring the marines back.
India said it is considering what steps to take next in the international dispute and is exploring the legal and diplomatic options it can pursue.
Foreign Secretary Ranjan Mathai, the top bureaucrat in India's ministry of external affairs, said he told the Italian ambassador in New Delhi that Italy's position was unacceptable to India.
Mathai said he told Daniele Mancini that India expects "Italy as a country that is committed to the rule of law, to fulfill the sovereign undertaking given by it to the Supreme Court of India."
Earlier Tuesday, the Minister for External Affairs Salman Khurshid had said the government would respond appropriately to a letter from the Italian government saying the marines would not return to India.
But opposition political parties said the decision showed Italy did not take the Indian government seriously.
"This is a betrayal by the Italian government," said Rajiv Pratap Rudy, spokesman of the main opposition Bharatiya Janata Party. "It is a breach of trust between two sovereign nations and the act is completely unacceptable."
Rudy said the government should make all out efforts to bring the marines back to face "trial under Indian laws and in Indian courts."
The marines, Massimilian Latorre and Salvatore Girone, were part of a military security team aboard a cargo ship when they opened fire on a fishing boat in February last year that they said they mistook for a pirate craft, killing the two fishermen. The shooting took place off the coast of India's southern state of Kerala.
On Tuesday, lawmakers from Kerala met with Prime Minister Manmohan Singh to urge him to ensure justice for the families of the fishermen.
The wife of one of the slain fishermen said the decision to let the marines go home to vote appeared to be part of a plan to spare them from facing trial.
"This is nothing but a conspiracy at the highest level," said the wife, Dora Valantine. "The Indian government should ensure that they bring back the two and make them stand trial in this country."
Last year, Italy paid compensation of 10 million rupees ($192,308) each to the families of the fishermen.
The marines said they had put their faith in the Italian government to help them out.
"I knew that our government wasn't abandoning us. It wouldn't abandon us. They gave us four weeks from when we returned to Italy to vote, and I felt that something would happen, something positive, I mean," Girone was quoted as saying by the Milan daily Corriere della Sera.
But he said they were not celebrating their release. "There isn't anything to celebrate. Our case is not over yet," Girone said.
The incident sparked a diplomatic dispute between the countries. Italy maintains the shooting occurred in international waters and that Rome should have jurisdiction. India says the ship was in Indian territorial waters.
The Indian Supreme Court ruled earlier this year that the men should be tried by a special court to be set up by the central government in consultation with the chief justice. The decision removed the case from the jurisdiction of the state of Kerala.
The Indian government had earlier allowed the marines to go home over the Christmas holidays, after which they returned to India.
In February, India's Supreme Court allowed them to return home to vote after the Italian ambassador to India gave a guarantee that the marines would be back.
The Italian government came under attack in that country's media on Tuesday.
The Rome daily La Repubblica said the move by Premier Mario Monti's caretaker government "dealt a terrible blow to our credibility from the point of view of international image."
The newspaper said the decision made the fishermen victims twice. "First by the tragic misunderstanding, then by a fraudulent behavior on the part of a country that should in any case take responsibility for what happened."
Italy said Monday that India's decision to try the marines would violate their rights, in particular the principle of immunity for foreign state actors, and that they would not go back.
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