South Sudan's brutal civil war has left almost 400,000 people dead, a new study by a British university said yesterday, an estimate about eight times the figure usually cited.

The research, carried out by the London School of Hygiene and Tropical Medicine and funded by the U.S. State Department, also counted people who had not died violently, but from the side effects of war, such as disease and lack of healthcare. Of the 400,000 victims of war, about half died violent deaths, said the report, which used an "innovative statistical approach to predict deaths which were attributable to crisis."

The previous death toll given for South Sudan's nearly five-year civil war, likewise an estimate but the one most commonly used by the media, United Nations and other groups, stood at about 50,000. However, analysts have always suggested it could be much higher.

"It is clear that the war has severely affected the health of the South Sudanese population, and that the humanitarian response to the crisis has been insufficient," Francesco Checchi, the professor who led the study, said in a statement.

South Sudan, the world's youngest country, descended into civil war in 2013 after President Salva Kiir accused rebel leader Riek Machar, then his deputy, of plotting a coup.

About 4 million South Sudanese have since fled the fighting and rights groups have documented numerous atrocities on both sides. The warring factions recently agreed to a peace deal, though previous attempts at lasting ceasefires have failed

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