Iran's official news agency said Tuesday that more than 15 Iranian and foreign nationals have been arrested for attempted assassination and sabotage, as well as allegedly spying for Israel. The IRNA report says the group planned to assassinate an "Iranian expert," whose field was not identified, as well sabotage the country's infrastructure. It also claimed the group used Israeli diplomatic missions in Western countries to prepare plans. In the past, several Iranian nuclear scientists have been killed by unknown assailants. The latest report did not elaborate on nationality of the foreign detainees. It claimed Iranian intelligence also uncovered a spy base belonging to Israel's Mossad in a neighboring country. Israel's Foreign Ministry refused to comment. In the past few months reports have surfaced that Israel's foreign intelligence service operates out of Azerbaijan, which borders Iran to its north. In February 2012, Israeli defense officials confirmed the completion of a $1.6 billion deal to sell drones and anti-aircraft and missile defense systems to Azerbaijan, bringing sophisticated Israeli technology to Irans doorstep. In late March, senior American diplomats and military intelligence officers told Foreign Policy magazine that the U.S. believes that Israel has been granted access to air bases in Azerbaijan. The Israelis have bought an airfield, a senior official told Foreign Policy in early February, and the airfield is called Azerbaijan. Speaking to Foreign Policy, one of the U.S. sources said, Were watching what Iran does closely. But were now watching what Israel is doing in Azerbaijan. And were not happy about it. In early March, security services in Azerbaijan arrested 22 people they say were hired by Iran to carry out terrorist attacks against the U.S. and Israeli embassies as well as Western-linked groups and companies.