Man is a social animal. They live in groups and they cannot survive alone, so that they can reproduce all the seasons throughout a year, which is uncommon among other animals that mate only particular season in a year's time.
To conquer or suppress other groups, one group needs to kill other groups that is what happening throughout the evolution of mankind. Who kills more, wins the war!! The sad thing is, it still continues in the world now, especially in Sri Lanka, where Sinhalese majorities kill minority Tamils.
Lanka is a land that is connected with Tamil Nadu by shallow water. Sea separated Tamils, so few lives in Lanka, and the majority lives in Tamil Nadu. There are some other ethnic group lives in Lanka, called Sinhalese, they would have migrated from Orissa and their inhabitant in island is still a question.
When a person is killed, so many die along with him. Do you know how? One couple can multiply in few years. This is what bothers Sinhalese people. They kill as many as they can, so that they can keep control of Tamil population in Lanka. To catch a single man, Prabhakaran, why are they killing thousands of civilians? When a majority of people do not want to live under your control, it is better to leave them alone, so that both of them can live in peace.
If you want peace, Sinhala people can learn Tamil and Tamils can learn Sinhala. Do not force one to learn your language when you are not willing to do it!!
Tamil rebels cannot keep other Tamils as hostages because, Sinhala army is showering bombs without any discrimination between troops and civilians!! They may stop shelling by the force of other people who have humanity, but not on their own!! At the bottom they do not care for Tamils which is evident!!
Have love towards your own people!!