Iranian students storm UK Embassy in Tehran amid rising tensions

Hundreds of Iranian protesters stormed the British embassy in Tehran on Tuesday, throwing firebombs and ransacking offices, in the latest stark example of escalating tensions between the West and Iran ostensibly over its nuclear program.

Elements of the Iranian government appeared to at least tacitly condone the violent demonstration, which was observed by Iranian news reporters and television cameras. The protest came two days after Iran's parliament voted to expel Britain's envoy to Iran in retaliation for the United Kingdom's decision to join the United States and Canada in a new round of economic sanctions targeting Iran's petrochemical sector.

Calling the situation an outrage, the British foreign office vigorously protested the incursion, and said it holds the Iranian government responsible.

"This afternoon our two Embassy compounds in Tehran were stormed by several hundred people, putting the safety of our diplomats and their families at risk and causing extensive damage to our property," British Foreign Secretary William Hague said in a statement emailed to journalists. "We hold the Iranian government responsible for its failure to take adequate measure to protect our Embassy, as it is required to do."

President Obama, in remarks with visiting Dutch Prime Minister Rutte, called the attack disturbing and urged Iran to punish the responsible parties.

"All of us, I think are deeply disturbed by the crashing of the English embassy," Obama said before his meeting with Rutte at the White House Tuesday. "That kind of behavior is not acceptable. And I strongly urge the Iranian government to hold those who are responsible to task."

"For rioters, essentially, to be able to overrun the embassy and set it on fire is an indication that the Iranian government is not taking its international obligations seriously," Obama also said. "And so, obviously, we're deeply concerned about that situation and we expect to see some sort of definitive action sometime very quickly."

The United States has not had diplomatic relations with Iran since the 1979 Iranian seizure of the American embassy and subsequent holding of 55 American hostages for over a year.

The Tehran embassy skirmish Tuesday comes as Washington and European allies have called for ratcheting up international sanctions on Iran to try to curb its nuclear program. The steps follow the release of a new International Atomic Energy Agency (IAEA) report this month that alleged Iran had conducted nuclear military research. Iran has insisted its nuclear program is only for peaceful energy purposes.

American officials have stressed in recent weeks that the situation has grown urgent.

"Tehran can choose a different direction. It has to seize the diplomatic opportunities before it," President Obama's National Security Adviser Tom Donilon told an audience at the Brookings Institution last week. But if Tehran does not change course, he warned, "the pressure will continue to grow," through deepened diplomatic and economic isolation and stronger Persian Gulf defense cooperation with the United States. In addition to obtaining full co-operation with IAEA officials, U.S. diplomats are pressing for full enforcement of several UN Security Council resolutions demanding Iran suspend its nuclear enrichment activities.

The UK Embassy protest also comes in the wake of two incidents this month of reported explosions near Iranian military installations.

In the first such episode, satellite images obtained by the nuclear non-proliferation research group ISIS show substantial damage sustained in a November 12 explosion at an Iranian military base in Bid Kaneh, near Tehran. The blast reportedly killed an Iranian Revolutionary Guards Corps officer described as a key figure in Iran's long-range missile program. And there were conflicting reports Monday regarding an alleged explosion heard in the Iranian city of Isfahan, near one of the country's nuclear facilities.

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