TEHRAN, Oct. 6 (Xinhua) -- Iran arrested four people who attempted to carry out sabotage in the country's nuclear establishments, Iran Atomic Energy Organisation (IAEO) chief, Ali- Akbar Salehi, said on Sunday.
"Some time ago, we could recognize four suspects in the IAEO, but we did not arrest them so that we could gather more intelligence from them," Salehi was quoted as saying by semi- official Fars news agency.
"We arrested them several days ago in the appropriate time," he said, adding that "We have started their interrogation."
Salehi did not say which nuclear establishments were the target of the plots but cautioned the Iranian security officials to be careful about the infiltrations through the border zones of the country.
Further details about the sabotage will be disclosed in due time, he added.
In the past days, security officials thwarted a number of " serious" plots against the country and such attempts are likely to hit the country, he was quoted as saying.
The enemy has always been plotting to strike our nuclear establishments, therefore the security unit of the IAEO has grave responsibility in protecting the organization.
"Iran's nuclear establishments are still the target of the cyber attacks, but, after the Stuxnet virus incident, we have promoted our protecting systems and are careful about possible threats," said Salehi.
Over the past years, Iran has been the target of numerous cyber attacks which aimed to disrupt the country's nuclear systems.
In July 2012, the reports said that two of Iran's uranium- enrichment plants were struck by cyber attacks, which shut down their computers. The reports said the AC/DC virus closed down the automation network at Iran's Natanz and Fordow facilities.
Iranian Intelligence Ministry announced in October 2010 that Iran had detected and thwarted the Stuxnet virus aimed at infecting the country's nuclear plant system.
Iran said the computer worm, Stuxnet, infected 30,000 IP addresses in Iran, including the personal computers of the staff at the country's first nuclear power plant, Bushehr.
Iran has accused the United States and Israel of being behind the cyber attacks.