A former United States retired general said that Hamas’ Oct. 7 attack on Israel is worse than 9/11 attacks.

Former Director of the Central Intelligence Agency retired Gen. David Petraeus —while speaking during an interview on CBS Sunday Morning— maintained that Israel’s casualties, when adjusted for the difference in population size, make the attack worse than the 9/11 attacks.

“This is far worse than 9/11,” Petraeus said. “This is the equivalent of the U.S. having experienced over 40,000 losses, rather than the 3,000 terrible losses that we sustained in the attacks of 9/11.”

Petraeus, who led the U.S.’ wars in Iraq and Afghanistan, added that he was shocked by the complexity of the attack, which has seen over 1,400 Israeli and American citizens murdered by Hamas terrorists.

Petraeus revealed that while the sophistication of the attack surprised him, he was more surprised that there was an awareness of what Hamas was planning before the terror organization’s attack. Petraeus added that he could not understand how U.S. and Israeli intelligence missed Hamas’ preparation for the attack.

“This is a very substantial operation, and the planning of it alone would have been very considerable; then, the training and equipping and positioning of forces, then the actual conduct of it,” Petraeus said. “That all of that could take place and not spark much increased military readiness is really quite stunning.”

Petraeus credited Hamas’ successful attack on Israel to “dramatic improvements” in the terror group’s operational security. He added that Hamas’ creative use of munitions to degrade, and in some cases knock out, the Israeli ability to see what was going across its border aided the attack.

The attack prompted Israel to declare war on Hamas, with the Jewish State launching thousands of rockets into the Gaza Strip. Israel is now preparing for a ground invasion of the Gaza Strip. Petraeus revealed that Israeli fighters face a daunting task in Gaza.

“This is going to be a very, very tough fight,” Petraeus said. “There are tunnels; there will be rooms that will have improvised explosive devices. You have to clear every building, every floor, every room, every basement, every tunnel. Civilian losses are inevitable, and tough Israeli losses lie ahead as well.”