Tehran, Iran (CNN) -- Iran arrested suspects in a bombing a year ago that killed a nuclear scientist, an attack Iran said was the work of "a spying and terrorist network" connected to Israel's intelligence agency, the semi-official Fars news agency reported.
Massoud Ali-Mohammadi was riding his motorcycle near his Tehran home on the morning of January 12, 2010 when a remote-controlled bomb planted on the bike detonated, a police investigator said last year.
Iran's intelligence ministry issued a statement that Fars published Monday which claimed the investigation and arrests led to Israel's Mossad agency.
"Following extensive security measures and precise monitoring of information and thanks to God's graces, the intelligence ministry forces succeeded in identifying and arresting the main elements responsible for this terrorist crime and disbanded a spying and terrorist network affiliated to the Qods Occupying regime (Israel)," the statement said.
Iran's Foreign Ministry accused Israel and the United States of involvement from the first day of the attack a year ago, saying it "revealed signs of the involvement of the Zionist regime, the U.S. and their allies in Iran."
A senior U.S. administration official said then that charges that the United States was behind the killing were "absurd."
There was no immediate response from the Israeli government.
The Iranian statement published Monday said Iran has uncovered "vital information about Mossad's infiltration and operations in the country, and vowed to reveal some relevant details in due time in future."
"Mossad has used its bases in a number of European states and even a number of Iran's neighboring countries to back up and lead assassination of Ali-Mohammadi," Iran said.
Ali-Mohammadi, 50, an Iranian university professor and nuclear scientist, was in front of his house in Qeytariyeh neighborhood in northern Tehran when the explosion killed him, Iranian security officials said.