The World Health Organisation chief said Thursday that the UN agency had confirmed recent attacks on a hospital in Iran, while multiple health facilities were damaged in the unrest, leaving dozens of paramedics injured.

"I am deeply concerned by multiple reports of health personnel and medical facilities in Iran being impacted by the recent insecurity, and prevented from delivering their essential services to people requiring care," Tedros Adhanom Ghebreyesus said on X.

He pointed to reports in recent days of "health workers assaulted, and at least five doctors detained, while treating injured patients".

"I call for the release of any health worker in detention. Healthcare personnel should never face intimidation," he insisted.

Protests broke out in Iran in late December over economic grievances, but turned into a mass movement against the Islamic Republic, with huge street demonstrations for several days earlier this month.

Rights groups have accused authorities of killing thousands in an unprecedented crackdown under the cover of an ongoing internet shutdown, while Iranian authorities say the violence was caused by "rioters" spurred by the United States and Israel.