The Mossad doesn’t mess around.

TEHRAN, Iran (AP) — 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 another person Wednesday, state TV reported. The slayings suggest a widening covert effort to set back Iran’s atomic program.

The attack in Tehran bore a strong resemblance to earlier killings of scientists working on the Iranian nuclear program. It is certain to amplify authorities’ claims of clandestine operations by Western powers and their allies to halt Iran’s nuclear advances.

The blast killed Mostafa Ahmadi Roshan, a chemistry expert and a director of the Natanz uranium enrichment facility in central Iran, state TV reported. State news agency IRNA said Roshan had “organizational links” to Iran’s nuclear agency, which suggests a direct role in key aspects of the program.

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.