Mohammad Javad Azari Jahromi said in a short Twitter post that the attack was “identified and defused by a cybersecurity shield,” and that the “spying servers were identified and the hackers were also tracked,” AP wrote.

Last Wednesday, Azari Jahromi said a “massive” and “governmental” cyberattack also targeted Iran’s electronic infrastructure. He provided no specifics on the attack except to say it was also defused and that a report would be released.

On Tuesday, the minister dismissed reports of hacking operations targeting Iranian banks, including local media reports that accounts of millions of customers of Iranian banks were hacked.

This is not the first time Iran says it has defused a cyberattack, though it has disconnected much of its infrastructure from the Internet after the Stuxnet computer virus, widely believed to be a joint US-Israeli creation, attacked thousands of Iranian centrifuges in the country’s nuclear sites in the late 2000s.

In June, American officials claimed that US military cyber forces launched a strike against Iranian military computer systems as President Donald Trump backed away from plans for a more conventional military strike in response to Iran’s downing of a US spy drone in the strategic Persian Gulf.

Tensions have escalated between the US and Iran ever since Trump withdrew America last year from the 2015 nuclear deal with Tehran and began a policy of “maximum pressure.” Iran has since been hit by multiple rounds of sanctions.