First, the Indian government isn't taking sides in the Sri Lankan conflict. Second, the LTTE are indeed a threat to India. Anybody who dares to assault Indian citizens in their own waters ought to be blasted away. Hence it is the duty of the navy and the coast guard to ensure the protection of Indian Tamil fisherfolk.
Lastly, stop trying to portray the LTTE as brave soldiers who fight for the Sri Lankan Tamil cause. They are a bunch of rabid killers. They kill indiscriminately may it be sinhalese, other Tamils, opposing groups, Indians etc.
P.S. I am neither Tamil nor Sinhalese so I'm not taking sides either. I am against the Sinhala opression of Tamils back in the day. However the way the LTTE is going about trying to attain their objective is not the way... and needless to say I have no sympathy for them or "their cause"