The Iranian government arrested four people for trying to sabotage a nuclear site, a senior official said Sunday.
Quoted by local media, Ali Akbar Salehi, the head of Iran's Atomic Energy Organisation, said that the activities of those arrested had been monitored for some time.
They had been caught red-handed, Ali Akbar Salehi said, according to a BBC report.
Salehi did not give details of their nationality or identify which site was the intended target, the BBC said.
Salehi's announcement comes amid revived hopes of resolving Iran's standoff with the West over its alleged nuclear programme.
Just over a week ago, Iran's President Hassan Rouhani spoke to US President Barack Obama in a landmark phonecall in a bid to ease tension over the Islamic Republic's nuclear programme.
The phonecall was the first instance of talks between Iranian and US leaders in over three decades, according to the BBC.
Nuclear negotiations between Iran and international powers are scheduled to take place next week and Rouhani has said he will bring a plan for Iran's nuclear weapons to the meeting.
Iran wants the UN to lift its sanctions on the country, which were imposed on the Islamic Republic over international concerns that Iran was building its nuclear capabilities in secret, according to the BBC. Tehran denies all allegations.