The United Nations said Tuesday it was "seriously concerned" by Malaysia's continued deportation of asylum-seekers from Myanmar back to their country.
UNHCR, the UN's refugee agency, said it had received "multiple disturbing reports" of refoulement – the forcible return of refugees and asylum seekers – since April.
In the last two months, hundreds of Myanmar nationals are reported to have been sent back against their will by the authorities, UNHCR said.
"UNHCR continues to call on Malaysia to immediately stop the forced returns of Myanmar nationals seeking safety from serious harm. Sending them back to Myanmar exposes them to harm and danger," spokesman Shabia Mantoo told reporters in Geneva.
"People fleeing Myanmar must be allowed access to territory to seek asylum and be protected against refoulement. Myanmar nationals already abroad should not be forced to return when seeking international protection."
Myanmar has been in turmoil since a military coup last year, with swathes of the Southeast Asian nation engulfed by fighting.
More than 2,300 people have been killed in the military's crackdown on dissent since the coup, which rights groups say includes razing villages, mass extrajudicial killings and air strikes on civilians.
The junta blames anti-coup fighters for the deaths of almost 3,900 civilians.
"The situation in Myanmar is forcing people to flee to seek safety within the country and across borders. UNHCR appeals to the Malaysian authorities to abide by their international legal obligations and ensure the full respect for the rights of people in need of international protection," said Mantoo.
"We reiterate our call on states in the region to continue offering protection to Myanmar nationals fleeing for safety. This also includes ending the practice of indefinite detention of asylum seekers and refugees from Myanmar."
Foreign ministers from the region will hold emergency talks to discuss Myanmar ahead of November's Asean leaders' summit.
Asean has spearheaded so far fruitless efforts to resolve the crisis, and the bloc is frustrated by escalating human rights atrocities.