HONG KONG (AP) — Clashes broke out Sunday between Hong Kong police and protesters at a rally in support of China's Uighur minority.

Police arrested two protesters who were attempting to burn a Chinese flag at the rally, which was attended by several hundred people.

Some were holding signs emblazoned with the blue and white flag of the independence movement in the northwestern Chinese territory of Xinjiang.

China has been accused of a mass crackdown against Uighurs and other predominantly Muslim minorities in Xinjiang, with reports of millions being held in heavily secured, prison-like camps.

Chinese diplomats have claimed that China holds no political prisoners and insist the centers provide vocational education as a bulwark against religious extremism.

Hong Kong, a semi-autonomous Chinese territory, has been in the grip of a pro-democracy movement for the past six months, with many protesters finding common cause with human rights movements elsewhere in China and beyond.