Mysterious blast in Iranian capital leaves one dead, injures two. Local media reports say blast ‘reminiscent’ of previous attacks on nuclear scientists.

According to Iranian media reports, the incident “looks similar to attacks on nuclear scientists in the city,” more than one year ago. The semi-official Fars news agency cited witnesses as saying a motorcyclist stuck a bomb on the side of the car which then exploded, killing one and injuring two people inside.

Fars identified the victim as Mostafa Ahmadi-Roshan. State-run Press TV said he was a university professor. Another Iranian nuclear professor was killed earlier this year when a motorcycle rigged with explosives was detonated outside his home. Iranian authorities, who claim Western governments seeking to thwart the country’s nuclear ambitions are behind the attacks on nuclear scientists, issued a statement blaming today’s attacks on “Zionist agents” and vowing revenge.

The U.S. and its allies are pressuring Iran to halt uranium enrichment, a key element of the nuclear program that the West suspects is aimed at producing atomic weapons. Uranium enriched to low levels can be used as nuclear fuel but at higher levels, it can be used as material for a nuclear warhead.

Iran has claimed that Israel’s Mossad, the CIA and Britain’s spy agency are engaged in an underground “terrorism” campaign against nuclear-related targets, including at least three slayings since early 2010 and the release of a malicious computer virus known at Stuxnet in 2010 that Iran says disrupted controls of some centrifuges a key component in nuclear fuel production. Both countries have denied the Iranian accusations.

Israeli officials have hinted about covert campaigns against Iran without directly admitting involvement. On Tuesday, Israeli military chief Lt. Gen. Benny Gantz was quoted as telling a parliamentary panel that 2012 would be a “critical year” for Iran in part because of “things that happen to it unnaturally.”

“Many bad things have been happening to Iran in the recent period,” added Mickey Segal, a former director of the Israeli military’s Iranian intelligence department. “Iran is in a situation where pressure on it is mounting, and the latest assassination joins the pressure that the Iranian regime is facing.”