TEHRAN, Iran — Two assailants on a motorcycle attached a magnetic bomb to the car of an Iranian university professor working at a key nuclear facility, killing him and wounding two people on Wednesday, a semiofficial news agency reported.

The attack in Tehran bore a strong resemblance to earlier killings of scientists working on the Iranian nuclear program. It is certain to reinforce authorities’ claims of widening clandestine operations by Western powers and allies to try to cripple nuclear advancements.

The bomb killed Mostafa Ahmadi Roshan, a chemistry expert and a director of the Natanz uranium enrichment facility in central Iran, the semiofficial Fars news agency reported. Natanz is Iran’s main enrichment site, but officials claimed earlier this week that they are expanding some operations to an underground site south of Tehran with more advanced equipment.

Witnesses told Reuters they had seen two people on the motorcycle fix a bomb to the car.

“The bomb was a magnetic one and the same as the ones previously used for the assassination of the scientists, and is the work of the (Israelis),” Fars quoted Tehran’s Deputy Governor Safarali Baratloo as saying. “The terrorist attack is a conspiracy to undermine the (March 2) parliamentary elections.”

‘Our path is irreversible’
Iran’s Atomic Energy Organization said the country’s nuclear path would not change despite the killing, which it branded a “heinous act”.

CONTINUED at MSNBC.