Iranian protesters stormed the British embassy in Tehran Tuesday following new British economic sanctions against Iran over its alleged nuclear weapons program.

The protesters pushed their way past security and onto the large embassy compound, chanting, “Death to Britain.” They smashed windows, set fire to a car, and threw documents out of the building. One protester pulled down the British flag while another stole a portrait of Queen Elizabeth.

Another group of Iranians also stormed a British diplomatic office in northern Tehran and briefly surrounded six people. British authorities did not regard the six as hostages and said all diplomatic personnel in Tehran have been accounted for.

British Prime Minister David Cameron says he is outraged over what happened in Tehran. He says the Iranian government's failure to defend British staff and property is a disgrace and is holding it responsible.

The White House says U.S. President Barack Obama is deeply disturbed by the attack. France is also condemning the incident.

Last week, Britain cut business transactions with all banks in Iran, including the Central Bank, as part of sanctions with the United States and Canada. The move was in response to Iran's suspected program to build nuclear weapons. It was the first time Britain has cut ties with the entire banking sector of a country.

The new sanctions followed a new United Nations atomic energy agency report saying Iran is likely researching nuclear weapons. Tehran insists its nuclear activities are for civilian purposes.

Iran's parliament Sunday passed a bill to reduce diplomatic and economic ties with Britain. The British ambassador must go within two weeks, leaving a charge d'affaires to run the embassy. Economic relations with London will also be reduced to a minimum.