Members of Iranian Police special forces Reuters

Iran has released more details about what it says was Israel-backed terror plot broken up last week, including the revelation that 15 people, accused of being Iranian and foreign spies, were arrested for planning to assassinate an Iranian expert.

A report in Iran's official Press TV did not identity the field of the targeted expert, but four nuclear scientists have been assassinated in Iran in as many years. Tehran has repeatedly blamed Israeli spy agency Mossad for planting the car bombs that killed experts like Mostafa Ahmadi Roshan, a university chemistry professor who doubled as a director of Iran's Natanz uranium-enrichment facility, who was assassinated in January. Israel has neither denied nor confirmed the allegations.

Iranian officials said on Tuesday that the Mossad-linked spies and terrorists were trying to identify and assassinate one of our nation's experts and to bomb some of the nation's installations using professionally made technical tools, according to the Jewish Telegraph Agency.

The announcement comes after a report earlier this month that Iran's Intelligence Ministry had busted a network it described as large and sophisticated, Israeli-backed, and planning attacks inside Iran. On April 10, Tehran revealed that after months of investigation one of the biggest terror and sabotage networks of the Quds [Jerusalem] Occupying Regime [Israel] as well as operatives and ... criminal terrorists had been uncovered in a sting operation, without giving many more details.

The complicated and months-long measures and moves made by the Iranian intelligence forces to identify the devils led to the discovery of the Zionists' regional command center in one of the regional countries and discovering the identity of the agents active in that command center, the Intelligence ministry said in a statement at the time.

The Tehran Times said that some information couldn't be revealed due to security considerations.

The latest ministry report did claim that a Zionist regime’s spy base was found in a neighboring country which had been frequently used by Mossad to carry out operations against the interests of the Islamic Republic of Iran, although the country wasn't named.

Iran periodically announces the capture or execution of alleged US or Israeli spies, and often no further information is released, Israel's YNet News commented on Tuesday.