A day after U.S. officials warned of escalating Iranian cyberattacks, Prime Minister Benjamin Netanyahu said Sunday that Israel, too, was being subjected to Iranian cyberwarfare.

"Many attempts are being made to infiltrate Israel's computerized systems," Netanyahu said at the start of the weekly cabinet meeting.

"Just as we have an Iron Dome missile interceptor to protect against missiles, and a border fence to prevent infiltrators and terrorists from entering, we will also have a similar defense against cyberattacks.

"For this purpose, I established the National Cyber Directorate a year ago and it has been working to block these attempts by developing what I would call a 'digital Iron Dome' to protect Israel from cyberwarfare."

Meanwhile, The Wall Street Journal reported this weekend that government-linked Iranian hackers were responsible for a series of cyberattacks against American targets in recent months.

These cyberattacks prompted U.S. Defense Secretary Leon Panetta to warn of an imminent "cyber-Pearl Harbor" in a speech he gave at the Intrepid Sea, Air and Space Museum in New York on Thursday.

The wave of cyberattacks peaked recently when American banks were breached and computers across the Saudi oil industry were crippled by hackers. In August, a computer virus destroyed data stored on some 30,000 computers belonging to the Saudi oil company Aramco. U.S. officials have voiced suspicions that these attacks were perpetrated by an organized Iranian group supported by the regime.

Investigators told The Wall Street Journal that a group of less than 100 Iranian computer experts was apparently behind the attacks. According to the report, the attack bore signatures that could be traced back to the Iranian government. A security source revealed that the Iranians had set their sights on American financial institutions, including Wall Street. The U.S. security establishment views these cyberattacks as a part of a wider Iranian war effort, which includes physical terror attacks carried out by Iran's proxies around the world.

"In the last year, there's been a cyberwar going on in the Middle East, and it's spilled over now" into America, a former U.S. official told The Wall Street Journal.

Panetta addressed the issue on Thursday, saying that it was something that needed to be taken very seriously. He described the combination of cyber and physical attacks as a "cyber-Pearl Harbor" that would cause physical destruction and the loss of life, an attack that would “paralyze and shock the nation and create a profound new sense of vulnerability."

“An aggressor nation or extremist group could use these kinds of cybertools to gain control of critical switches. They could derail passenger trains, or even more dangerous, derail passenger trains loaded with lethal chemicals. They could contaminate the water supply in major cities, or shut down the power grid across large parts of the country," Panetta said.

Such an attack could be "as destructive as the terrorist attack of 9/11,” Panetta said.

Meanwhile, Shai Blitzblau, the head of Maglan-Computer Warfare and Network Intelligence Labs, said Saturday that he believed the attacks were "not perpetrated by Iran, but rather a group of Muslim hackers."