JAKARTA, Indonesia -- A watchdog group on Monday criticized Indonesia over its treatment of children who are migrants or seeking asylum, saying they are placed in abysmal conditions with no way of appealing their detention.

The New York-based Human Rights Watch said in a released Monday that Indonesia has detained hundreds of migrant and asylum-seeking children each year without giving them a way to challenge their detention. The country lacks asylum laws and allows immigrants to be detained for up to 10 years.

"Hundreds are detained in sordid conditions, without access to lawyers, and sometimes beaten. Others are left to fend for themselves, without any assistance with food or shelter," the report said.

The group said there are almost 2,000 asylum-seeking and refugee children in Indonesia as of March, and that more than 1,000 arrived in 2012. They are fleeing persecution, violence, and poverty in Somalia, Afghanistan, Pakistan, Burma and elsewhere.

The report was based on interviews with more than 100 migrants, including children as young as 5, as well as Indonesian officials and staff members of nongovernmental and intergovernmental organizations.

It said both adults and children described abuse by guards or other detainees, including being kicked, punched, beaten with sticks, burned with cigarettes and subject to electric shocks.

In one case, the report quotes parents as saying immigration guards forced their children, including a 4-year-old and 6-year-old, to watch guards beat other migrants.

Alice Farmer, the group's children's rights researcher, said migrant and asylum-seeking children risk life and limb to flee their countries.

"Yet the port in the storm Indonesia offers is squalid detention facilities, where children waste months or years without education or hope for the future," she said.

"Migrant children in Indonesia are trapped in a prolonged waiting game with no certain outcome," added Farmer. "Desperate children will keep coming to Indonesia, and the government should step up to give them decent care."

Indonesia, the world's largest archipelagic nation with thousands of islands and kilometres of unpatrolled coastline, is a key transit point for smuggling migrants.

Hundreds of asylum-seekers from war-ravaged countries have died in sea accidents on the hazardous sea journey from Indonesia to Australia.