Former undersecretary of State Nicholas Burns, who oversaw America's Iran engagement during the Bush administration, asked Sunday about reports that the U.S. program began under George W. Bush, said he could not comment on intelligence matters.

Photos of an Iranian military base near Bid Kaneh in before (top) and after (bottom) a large explosion reportedly occurred, apparent damage from which can be seen / Institute for Science and International Security

In September, the head of the Atomic Energy Organization of Iran, Fereydoun Abbasi-Davani, accused Great Britain, Israel and the U.S. of conducting attacks on him and other Iranian scientists."Six years ago the intelligence service of the UK began collecting information and data regarding my past, my family, the number of children," Abbasi-Davani told a news conference at the annual conference of the International Atomic Energy Agency (IAEA) in Vienna. Abbasi-Davani, who was said to have been wounded in 2010 car bomb explosion, said the attacks were carried out by Israel with the "support of the intelligence services of the United States and England."

Last week, Iranian protesters stormed the British embassy in Tehran. Dominick Chilcott, Britain's ambassador to Iran, later said the attack occurred "with the acquiescence and the support of the state." Then, on Sunday, Bahrain's interior ministry announced that an explosion occurred inside a minibus parked near the British Embassy. There were no immediate reports of serious damage or injuries.



U.S. officials alleged in October that agents acting for Iran's Revolutionary Guard, which has increasingly exerted control over the Tehran regime, were involved in a plot to kill that Saudi ambassador to Washington in a restaurant. Iran denied the allegations. Then, on Sunday, in what have been another escalation, Iran's news agency reported that Iranian armed forces shot down an unmanned U.S. spy plane that illegally crossed the country's eastern border.

Responding to the Iranian report, NATO command in Afghanistan released a terse statement Sunday: "The UAV to which the Iranians are referring may be a US unarmed reconnaissance aircraft that had been flying a mission over western Afghanistan late last week. The operators of the UAV lost control of the aircraft and had been working to determine its status."

The White House declined to comment but officials did not seem unduly alarmed, suggesting that the drone's capture would not provide Iran with significant information about U.S. surveillance technology and techniques.

Trita Parsi, president of the National Iranian American Council in Washington, said the tit-for-tat incidents "add up to a very worrisome picture," in part because "the Iranians are absorbing all of these assassinations without seeing the pace of their nuclear program slow down to the extent it would be acceptable to the West." But if Iranian retaliations grow serious enough, he said, they could provide "the pretext for a much larger war" in which the Israelis, and possibly the Americans, launch a full attack on Iran.