New Delhi, April 1 - India's government said Monday that it was re-assigning the case of two Italian marines accused in the deaths last year of two Indian fishermen, from local authorities to its elite national investigating force. India's interior minister said that the case has been assigned to its National Investigation Agency (NIA), which will work with a special court that will outline its duties on Tuesday. The complex case has reached the highest political levels, has led to the resignation of Italy's foreign minister, and caused a diplomatic rift between the two countries over the fate of the marines. "Everything will happen tomorrow," the Indian source told ANSA on Monday. The NIA is India's top investigating force that often tackles terrorism cases but also has responsibility for criminal offences at sea. Last week, Giulio Terzi resigned as Italy's foreign minister in protest over the Italian cabinet's decision to return to the marines to face homicide charges in India. That action followed days of diplomatic wrangling with New Delhi over an earlier decision not to return Massimiliano Latorre and Salvatore Girone for trial when a four-week parole period for the pair expired on March 22. They are accused of shooting and killing two Indian fishermen after allegedly mistaking them for pirates during an anti-piracy mission off the Kerala coast in February 2012. Italy has consistently disagreed with India's claim that it has jurisdiction over the case, arguing that the deaths occurred in international waters. Meanwhile in Rome, ex-premier Silvio Berlusconi's People of Freedom (PdL) political party said in a note Monday that the caretaker government of outgoing Premier Mario Monti did not have the authority to send the marines back to India.