A U.N. investigative team that will collect and preserve evidence of acts by Islamic State in Iraq that may be war crimes, crimes against humanity or genocide started work this week, nearly a year after the Security Council created it.

At last September’s annual U.N. gathering of world leaders, the council unanimously adopted a British-drafted resolution – after a year of talks with Iraq – asking U.N. Secretary-General Antonio Guterres to create the team “to support domestic efforts” to hold the militants accountable.

U.N. experts had warned in June 2016 that Islamic State was committing genocide against the Yazidis in Syria and Iraq to destroy the minority religious community through killings, sexual slavery and other crimes.

Guterres notified the 15-member Security Council in a letter that the U.N. team, led by British lawyer Karim Asad Ahmad Khan, would start work on Aug. 20.

Guterres announced in May that he had appointed Khan after the Security Council approved the scope and limitations for the team in February. He said in the letter, released on Thursday, that Khan visited Iraq earlier this month.

Use of evidence collected by the team in other venues, such as international courts, would “be determined in agreement with the Government of Iraq on a case-by-case basis.” Evidence is for primary use by Iraqi authorities, followed by “competent national-level courts,” according to the 2017 U.N. resolution.

International human rights lawyer Amal Clooney and Nadia Murad, a young Yazidi woman who was enslaved and raped by Islamic State fighters in Mosul, have long pushed Iraq to allow U.N. investigators to help.

Islamic State, which until last year controlled large areas in Syria and Iraq, has since been driven into the desert by successive defeats in offensives by international allies in both countries. The U.N. investigative team’s mission does not include Syria.

George and Amal Clooney said on Monday they would help 3,000 Syrian refugee children go to school this year in Lebanon, where the United Nations says 200,000 children are not receiving an education after fleeing the war in neighboring Syria.

The Clooney Foundation for Justice said it has teamed up with Google and HP Inc to help the U.N. children’s agency UNICEF and the Lebanese Ministry of Education open seven so-called “second shift” schools for Syrian refugee children.

Lebanon has more than 1 million Syrian refugees, including nearly 500,000 children. It is educating Syrian children in public schools through a “second shift” system of additional afternoon classes exclusively for them.

“We don’t want to lose an entire generation because they had the bad luck of being born in the wrong place at the wrong time,” said Oscar-winning actor George Clooney and international human rights lawyer Amal Clooney, who gave birth to twins last month.

“Thousands of young Syrian refugees are at risk – the risk of never being a productive part of society,” the couple said in a statement. “Formal education can help change that.”

A $3.25 million donation from the Clooney Foundation for Justice, Google and HP will pay for transportation, school supplies, computers, content, curriculum and teacher training.

A spokesman for the Clooneys’ foundation, Max Gleischman, said the organization had decided to support education for Syrian refugees through the public school system, instead of investing in private schools operated by SABIS, an international company which has prepared students for college and high school exams.

The foundation had announced last year that it would work to enroll thousands of children in SABIS schools.

A crackdown by Syrian President Bashar al-Assad on pro-democracy protesters in 2011 led to civil war, and Islamic State militants used the chaos to seize territory in Syria and Iraq. Half of Syria’s 22 million people have been uprooted and more than 400,000 killed.

International human rights lawyer Amal Clooney will defend Yazidi women who have been victims of sexual slavery, rape and genocide by Islamic State militants in Iraq, her law firm said on Friday.

Clooney, a barrister at Doughty Street Chambers in London, is seeking to prosecute the Islamist group through the International Criminal Court for their crimes against the Yazidi community.

“We know that thousands of Yazidi civilians have been killed and that thousands of Yazidi women have been enslaved,” Clooney, who is married to actor George Clooney, said in a statement.

“We know that systematic rapes have taken place, and that they are still taking place,” Clooney said. “And yet no one is being held to account.”

Islamic State militants have killed, raped and enslaved thousands of Yazidis since 2014, accusing them of being devil worshippers and forcing over 400,000 of the religious minority to flee their homes in northern Iraq.

Yazidi campaigners, including Nobel Peace Prize nominee Nadia Murad Basee Taha, have been pushing for international justice for the crimes committed against them by Islamic State.

Taha, 21, took her message to the U.N. Security Council in December last year, and has spoken to successive governments, appealing to the international community to act.

Taha said she was abducted by Islamic State militants from her village in Iraq in August 2014, and taken to the Islamic State stronghold of Mosul, where she and thousands of other Yazidi women and children were exchanged by militants as gifts.

She was tortured and repeatedly raped before she escaped three months later.

According to the United Nations, the Sunni militants enslaved about 7,000 women and girls in 2014, mainly Yazidis whose faith blends elements of Christianity, Zoroastrianism and Islam, and is still holding 3,500, some as sex slaves.

The United States, the European Parliament and the Council of Europe have all described the Islamist militant group’s actions as genocide.