COLOMBO: Sri Lanka has for the first time made public its heavy casualties from the last phase of the 25-year war, as the UN chief flew to the island on Friday to push for a rapid end to a lingering humanitarian crisis.

Officials said over 6,000 soldiers were killed and nearly 30,000 injured since a battle in July 2006 that the military marks as the start of "Eelam War IV", the final stage of the war against the Liberation Tigers of Tamil Eelam (LTTE).

Sri Lanka declared total victory over the LTTE on Monday after killing off its leadership and remaining fighters in a climactic final battle in the northeast of the island.