SYDNEY, Australia — The body of an asylum seeker who was said to have been suffering depressive episodes was discovered on Monday by schoolchildren in Papua New Guinea, near the site of an Australian transit center for refugees, and the police said they believed he had hanged himself.

Manus Island, a part of Papua New Guinea, is home to one of two offshore centers where Australia has been housing asylum seekers intercepted at sea for the past four years. A United Nations report found that 88 percent of the detainees on Manus who were examined by medical experts last year had depressive disorders.

The asylum seekers have been sent to Manus and to Nauru, an island nation to the east, as part of a policy that Australia says is meant to deter human traffickers from sending desperate people to its shores on rickety boats, usually by way of Indonesia.

The Australian government has repeatedly said that no refugees would be allowed to resettle in Australia, drawing condemnation from the United Nations and human rights groups.