A brief timeline of Iranian cyberattacks on the U.S.
Investigators are probing whether Iranian hackers are behind this week's malicious cyber activity against water systems in Minnesota. If they are found to be the culprits, it would not be the first time.
For more than a decade, Iranian-linked operators have repeatedly hacked accessible American targets. They scan for widespread vulnerabilities and aim to create disruption, intimidate, gain publicity and undermine trust in the American government.
But official confirmation can take weeks or months as investigators collect technical evidence. Investigators are also looking into whether the actor could have attempted to appear Iran-based as a way of stirring the pot amid the U.S. war with Iran.
Iran has long denied any involvement in cyberattacks.
Here are some of the high-profile Iranian-linked cyberattacks in the U.S.:
Seven Iranians working for companies connected to the Iranian government and Islamic Revolutionary Guard Corps were charged a decade ago with distributed denial-of-service, or DDOS, attacks against 46 financial institutions between 2011 and 2013.