Iran has hanged a 24-year-old man whom it accused of being an agent for the Israeli intelligence agency Mossad and of killing one of its nuclear scientists.
The execution of Majid Jamali Fashi at Tehran's Evin Prison followed his conviction last August for murdering a Tehran University professor, Massoud Ali-Mohammadi,in January 2010.
State media said he had confessed to the crime, and reported at the time that the professor, 50, was killed when a remote-controlled bomb attached to a motorcycle was detonated outside his home in the north of the capital.
Iran accused the United States and Israel of being behind the attack, but Washington denied any involvement. Israel routinely refuses to discuss such accusations, which have since been levelled over the deaths of three more scientists.
The most recent attack claimed the life of Mostafa Ahmadi-Roshan, a deputy director of the Natanz uranium enrichment facility, who was killed in January by a magnetic bomb planted on his vehicle.
Iran's state media also announced that another "Zionist-regime-linked" conspiracy to murder an Iranian "specialist" had been foiled, with 15 people, including both foreigners and Iranians, arrested on suspicion of having participated in the plot.
It is unclear what role, if any, Professor Ali-Mohammadi had in what Israel and the West are convinced is Iran's effort to acquire a military nuclear capability.
The Tehran-based satellite channel Press TV said that Fashi - believed to be an Iranian citizen - had confessed to receiving training from Mossad and of being given US$120,000 to carry out the killing, and of using forged documents to allow him to travel to Tel Aviv.