After suspected Iranian hackers claimed a string of recent attacks on Israeli security cameras, Israel’s cyber defense chief told CNN he is “very concerned” that Iran could escalate its long-running covert battle with Israel in cyberspace with more serious attacks on infrastructure as the war between Israel and Hamas shows no sign of ending.

“They [Iran] know that they can act there more freely [in cyberspace] than in the physical space,” said Gaby Portnoy, the head of the Israel National Cyber Directorate. “We are prepared for that as much as we can.”

Portnoy said there would be a “cost” to any Iranian escalation in cyberspace, implying that Israeli hackers could retaliate against Iran with their own operations. But Portnoy, who is in charge of cyber defense and not offense, said his goal is to keep cyberspace from becoming “another front” in the war between Israel and Hamas.