This is a hell for children,” the letter reads. “I fled from war in Iraq but got stuck in harsh jail in Nauru where [there] is nothing but cruelty.”

The 15-year-old’s appeal is one of hundreds written by some of the 222 children, who are refugees or are seeking asylum in Australia, held on the tiny island nation of Nauru.

Many are impounded at camp OPC3, under the supervision of private Australian security firms. Conditions are dismal, and the inhabitants’ hopes of reaching Australia were dashed last week when the country inked a deal to resettle refugees in Cambodia.

In a series of submissions to the Australian Human Rights Commission’s ongoing inquiry into the country’s “off-shore processing” policy, children on Nauru have documented the suffering they endure in the camps.

“You’re nothing but a cult of racist liers [sic] [whose] aim is to kill the peoples even children on Nauru,” wrote one child. “Nauru is hell and you know everything about it … imagine [if] your children were in … our circumstances.”

Another child drew a row of dead refugees with nooses around their necks. Another, from Iran, scribbled a picture of Australian Prime Minister Tony Abbott shooting a refugee. “Neither Iran, nor Australia, has freedom,” the child wrote.

The children described cramped, stuffy accommodation, inedible food crawling with insects and a lack of basic necessities like water and medical care.

In another submission, a child protection worker described the allegations of sexual abuse at the hands of guards that have emerged from the camp.

“Children have been sexually assaulted and threatened with sexual assault, and they are not allowed to leave the camp, even with family members able to care for them here.”

“Everyone here is depressed,” wrote one child. “F—k my life.”

To view the submissions to the inquiry in full, visit www.humanrights.gov.au/our-work/asylum-seekers-and-refugees/national-inquiry-children-immigration-detention-2014-0