COLOMBO, March 25 (Xinhua) -- Over a dozen of Tamil Tiger rebels were killed and many injured in heavy fighting between the government troops and the rebels in northern Sri Lanka on Wednesday, the military said.

    Officials from the Defense Ministry said the LTTE (Liberation Tigers of Tamil Eealm) rebels were killed when the troops pushed back an attack launched by the rebels on the military forward defence line at North of Iranapalai in the Mullaittivu district around 5:30 a.m. local time (2400 GMT).

    Four senior rebels were among the dead, the military said, without releasing any casualty figure on the troops.

    The fighting came as the military say the LTTE have been confined to an area of just 20 sq km in Puthukkudiyiruppu from over 15,000 sq km they held in the north and east when the current military offensive began in 2006.

    The LTTE began to rebel against the government to set up a separate homeland for the minority Tamils in the north and east in the mid-1980s, based on claims that the minority Tamils had been discriminated by the majority Sinhalese dominated government.

    More than 70,000 people have died in the conflict since the mid-1980s in one of the world's longest civil wars.