Ambassadors of more than 20 countries have called on China to end its mass detention of ethnic Uighurs in the Xinjiang region.
The countries that criticized China's treatment of Uighur Muslims include Australia, Britain, Canada, France, Germany and Japan.
Read more: Anger boils over Xinjiang visit by UN counterterrorism chief
The unusual letter, dated July 8, was sent to Coly Seck, president of the Human Rights Council, and Michelle Bachelet, the high commissioner for human rights at the Council.
The letter decried "large-scale places of detention, as well as widespread surveillance and restrictions, particularly targeting Uighurs and other minorities in Xinjiang."
"We call on China to uphold its national laws and international obligations and to respect human rights and fundamental freedoms, including freedom of religion or belief in Xinjiang and across China," read the letter.
"We call also on China to refrain from the arbitrary detention and restrictions on freedom of movement of Uighurs, and other Muslim and minority communities in Xinjiang."
Activists had sought a formal resolution at the Council, but some analysts say the move was the only available option to spotlight the Uighur plight at the forum. China was thought to have enough votes to stop any resolution, hence the unusual step of an open letter of criticism from diplomats instead.
Read more: Uighur woman shares 'horrendous' China crackdown details with US Congress
inicization of Islam?
In October last year, Chinese authorities in the far-northwestern region of Xinjiang revised legislation to permit the use of "education and training centers" to combat religious extremism.
Rights groups say that in practice the centers are internment camps in which as many as 1 million minority Muslims have been placed in the past few years.
The Chinese measures have raised concerns among Muslims in other parts of China that Beijing wants to implement the Sinicization model across the country.
China says the camps are "training centers" to equip people with employable skills to help combat Islamist extremism in Xinjiang province, still the site of frequent violence.
Read more: China says 13,000 'terrorists' arrested in Xinjiang since 2014
The Chinese government has for decades tried to suppress pro-independence movements among Xinjiang's Muslim community, spurred largely by frustration over the influx of migrants from China's Han majority.
Chinese authorities say that extremists in the region have ties to terror groups, but have given little evidence to support that claim.
shs/msh (AFP, Reuters)
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