The United Nations said on Sunday it is alarmed at the “violent nature” of a demonstration in a massive Syrian refugee camp in Jordan that killed one person and wounded dozens.

Saturday’s deadly protest in the sprawling Zaatari camp reverberated around the region as international aid agencies and host governments struggle to cope and manage millions of Syrians who have fled the three-year-old conflict and sought shelter in neighbouring Iraq, Jordan, Lebanon and Turkey.

In a statement, the U.N. refugee agency said a “heated demonstration” in Zaatari turned to “a violent one” after possibly thousands of refugees started throwing rocks at a police post inside the camp. The protest started over a refugee family being held there after police detained them and a driver who tried to smuggle them out, the UNHCR said.

Jordan is home to 588,979 registered Syrians refugees, and the numbers grow daily.

Most of the Syrians are staying in two organised encampments near the northern border with Syria. With a population exceeding 120,000, Zaatari is the biggest camp. The refugees are under direct care of the United Nations and the Jordanian government.

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