Asylum seekers on a remote British military base island say they are being subjected to sexual assaults and harassment, according to UN investigators.

Dozens of Sri Lanka Tamils who say they are fleeing persecution at home are on Diego Garcia, an island in the Indian Ocean that is also a US military base.

They told UN investigators they feel unsafe and forgotten, and reported sexual assaults and harassment of children by other asylum seekers.

The claims were documented in a draft report by the UN refugee agency, which was released to the BBC by the British Indian Ocean Territory’s supreme court. Some asylum seekers have previously harmed themselves and attempted suicide.

The draft report says that conditions there amounted to arbitrary detention, and calls for the asylum seekers to be “urgently relocated”, according to the BBC.

Sri Lanka Tamils arrived on Diego Garcia in 2021 and 2022, when their boats ran into trouble and they were rescued by British forces. They reportedly said they were fleeing persecution by Sri Lankan and Indian authorities, some for alleged links to a separatist group that fought against the Sri Lankan government in a civil war that ended in 2009.

Some have since returned home, leaving 61 Tamils on Diego Garcia waiting for their asylum claims to be processed.

The visit by the inspectors from UNHCR, the UN refugee agency, was the first time an “external party” had gained access to the island to monitor conditions since the arrival of the Tamils, according to the BBC report.

UNHCR considers that the 61 Tamils on Diego Garcia “reside in a closed place with no possibility to leave at will, which amounts to detention under international law”, according to the BBC. Adults and children are held in a fenced area and are barred from leaving unless with a security escort, the report says. Inspectors saw signs of clinical depression and post-traumatic stress disorder.

“Living here is like living in hell,” the report quotes a mother as saying. “Children go to bed late and in [the] night do not sleep because they do not feel at peace. And that is because the children feel that we as parents are not at peace.”

The Foreign Office responded to the draft UNHCR report by saying: “[British Indian Ocean Territory, or BIOT] is not a suitable location for migrants, which is why we have been working tirelessly to process the migrants’ claims for protection and to find a suitable third country for those whose claims are upheld.

“At all times, the welfare and safety of migrants on BIOT has been our top priority.”

There was no immediate response from UNHCR to a request for comment on Sunday evening.

Diego Garcia is home to thousands of troops, but no civilian population since Islanders were removed in the 1970s to make way for the military base.