The United Nations High Commissioner for Human Rights Zeid Ra'ad Al Hussein has arrived in Sri Lanka amid concerns that the country's President Maithripala Sirisena is backtracking on promises to investigate war crimes.
Sri Lanka had committed to allow foreign judges to investigate allegations against Sri Lankan forces but last month Sirisena said that no foreign judges would be allowed in the investigation.
Sri Lankan troops are accused of killing at least 40,000 Tamil civilians in the final months of the civil war in 2009.
Al Hussein who is on a four day visit will travel to the former war zone and will meet victims of human rights violations reported Lanka Page website. He will also talk to top government officials, civil activists and religious leaders.
President Sirisena has said Sri Lanka does not need to 'import' specialists for an investigation.
In October 2015, Sri Lanka co sponsored a UN Human Rights Council resolution calling for a special judicial mechanism to prosecute war crimes.
Both the army and the Tamil Tiger rebels have been accused of atrocities in the civil war that ended in 2009.