Iran has arrested "some elements" who were working with Western spy agencies and connected to the murder of a senior Iranian nuclear scientist, Intelligence Minister Heydar Moslehi said on Thursday.
"The three spy agencies of Mossad, CIA and MI6 had a role in the (attacks) and, with the arrest of these people, we will find new clues to arrest other elements," Moslehi was quoted as saying on state television's website.
Moslehi did not say how many people were arrested or what specifically they are accused of. He only said they were a part of a "major group" that took part in the killing and that planned to carry out "widespread missions."
On Monday, unidentified assailants attached bombs to the cars of two prominent scientists in Iran's nuclear programme.
Twin blasts killed one, Majid Shahriari, and wounded the other, Fereydoon Abbasi Davani. Three other people were also wounded.
Iran immediately blamed the attacks on the intelligence services of the United States and Israel, which suspect Tehran's nuclear ambitions harbour a military dimension. The Islamic Republic denies the charge.