GENEVA (Reuters) - The conviction of former Bosnian Serb military commander Ratko Mladic for genocide and crimes against humanity serves as a warning to others such as Syrian President Bashar al-Assad, the United Nations’ human rights chief said on Wednesday.

Ex-Bosnian Serb wartime general Ratko Mladic reacts in court at the International Criminal Tribunal for the former Yugoslavia (ICTY) in the Hague, Netherlands in this still image taken from a video released by the International Criminal Tribunal for the former Yugoslavia (ICTY), November 22, 2017. International Criminal Tribunal for the former Yugoslavia (ICTY)/Handout via REUTERS

Earlier on Wednesday the U.N. Criminal Tribunal for the Former Yugoslavia (ICTY) found Mladic guilty of the slaughter of 8,000 Muslim men and boys at Srebrenica and for the siege of the Bosnian capital Sarajevo, in which more than 10,000 civilians were killed by shelling and snipers over 43 months.

U.N. High Commissioner for Human Rights Zeid Ra’ad al-Hussein, who worked for the United Nations in the former Yugoslavia in the 1990s, told Reuters he had waited a long time for the life sentence handed down against Mladic.

“Mladic is the epitome of evil and the prosecution of Mladic is the epitome of international justice,” Zeid said in an interview in his Geneva office.

Noting that Mladic is now 74 but was in his 50s at the time of his crimes, Zeid said the case showed justice would catch up with other leaders who trampled over human rights.

“The passage of time is no protection. Eventually I hope all those who have authored these appalling atrocities across the world will be held accountable before a court of law and there will be justice for the victims of those particular crimes.”

Pressed on whether that would include Assad, he said:

“Yes. It’s very clear to us that what happened in Syria recently and not limited to Syria, in many parts of the world, were so grotesque that if a court of law on the basis of evidence were to prosecute senior leaders then you would expect that some of them would be held responsible.”

Assad and his government deny committing rights abuses and say they are engaged in a legitimate struggle against terrorist groups including Islamic State.

Trials are led by evidence, Zeid said.

“And so whatever trials are mounted in the future, if the evidence leads to the very senior rungs of leadership, then you would indeed hope this takes place.”

“In the end there is justice,” he added.

U.N. war crimes investigators documenting massacres and other atrocities in Syria have accused all sides of grave crimes including the government’s use of chemical weapons against civilians more than two dozen times, as well as executions, torture and rapes.

Paulo Pinheiro, chairman of the U.N. Commission of Inquiry on Syria, said last year that the scale of deaths in prisons indicated that the Assad government was responsible for “extermination as a crime against humanity”.

Syria’s civil war, now in its seventh year, has killed hundreds of thousands of people and created the world’s worst refugee crisis, driving more than 11 million people from their homes.