SANA, Yemen — Turmoil in the Arab world linked to an American-made video denigrating the Prophet Muhammad spread on Thursday to Yemen, where hundreds of protesters attacked the United States Embassy, two days after assailants killed the American ambassador in Libya and crowds tried to overrun the embassy compound in Cairo.

News reports also spoke of a separate protest in Tehran, where around 500 Iranians chanting “Death to America” tried to converge on the Swiss Embassy, which handles United States interests in the absence of formal diplomatic relations with Washington. Hundreds of police officers held the crowds back from the diplomatic compound, witnesses said..

For a third straight day, protesters scuffled with police firing tear gas at the American Embassy in Cairo, witnesses said, and the state news agency reported that 13 people were injured. In Iraq, a militant Shiite group, Asaib Ahl al-Haq, once known for its violent attacks on Americans and other Westerners, reportedly said the video “will put all American interests in danger.” Protests were also reported at American missions in Morocco, Sudan and Tunisia, where police also fired tear gas to disperse crowds.

In Sana, witnesses said Yemeni security forces had tried to disperse a crowd at the fortified embassy compound in the east of Sana, the capital. But protesters broke through an outer perimeter protecting the embassy, clambering over a high wall and setting fire to a building.

They were forced to retreat after trying to plunder furniture and computers, the witnesses said.

Security forces guarding the embassy fired into the air as protesters set alight two vehicles and burned tires. Protesters tore down and burned an American flag, replacing it with their own banner proclaiming the Islamic faith, witnesses said.

There were no immediate reports of American casualties or that the protesters had managed to breach the main diplomatic buildings within the compound. Yemeni officials said an unspecified number of protesters were wounded and some were arrested. Hours after the attack started, smoke still rose from the area.

By early afternoon, one witness, Yahya Yousef, who lives opposite the embassy, said: “Now almost everyone is out, and firing has ceased. We saw protesters getting out with some stuff from inside.”

The protests came hours after a Muslim cleric, Abdul Majid al- Zandani, urged followers to emulate the protests in Libya and Egypt, Sana residents said. Mr. Zandani, a onetime mentor to Osama bin Laden, was named a ”specially designated global terrorist” by the United States Treasury Department in 2004.  Read more at New York Times.