Iranian security forces shot dead six militants in a clash in southeastern Iran, state-run Irna reported, adding that the group was linked to Israel.
The incident came a day after armed rebels killed five police officers in the region on Friday.
"One of the major terrorist plots in the eastern part of the country has been neutralised and the terrorist team responsible for it has been completely destroyed," the intelligence department of Sistan and Baluchestan said in a statement cited by Irna on Saturday.
The report claimed that the militants were not Iranian nationals and that it appeared they had received training by Israel's Mossad spy agency. It did not specify their nationality.
Two other members of the militant group were arrested, the report said.
"Based on the information obtained, the goal of this terrorist team was to attack one of the vital centres in the eastern region of the country," it added.
Iran's south-east has been the scene of sporadic clashes between security forces and armed groups, including Sunni militants and separatists who say they are fighting for greater rights and autonomy.
The crackdown on suspected Mossad agents or affiliates has intensified since the 12-day war with Israel in June. During the unprecedented war, Iran's police said it arrested 21,000 people as part of a campaign to tackle Israeli espionage.
There was no comment from Israel but Israeli intelligence officials openly bragged about how easily Iran could be infiltrated. Tehran pledged swift trials for suspects and has announced several executions for espionage.
