The U.N. human rights office says the death toll from the conflict in eastern Ukraine has reached at least 3,543 if the 298 victims of the downing of Malaysian airlines flight 17 are included.

U.N. Assistant Secretary-General for Human Right Ivan Simonovic says the actual figure "is likely to be significantly higher."

The death toll had previously been estimated to be about 3,000.

Simonovic told the U.N. Human Rights Council in Geneva on Tuesday that the global body has seen a sharp rise in killings, particularly between mid-July and the end of August.

By the time of the Sept. 5 cease-fire, an average of 42 people were being killed each day.

Since then that figure has decreased to fewer than 10 killings a day.