Iran and its allies are planning to launch a large-scale attack on Israel within the next 72 hours, CNN reported, citing officials from the U.S. Department of Defense.

Senior U.S. officials anticipate that the upcoming Iranian response will be very similar to the April 13 attack, but on a broader scale, likely involving Hezbollah, which did not participate in the previous assault.

The April 13 assault saw a combination of missile and drone attacks aimed at key Israeli military and strategic sites. Despite the intensity of the offensive, Israel's Iron Dome missile defense system intercepted many of the incoming projectiles, mitigating the potential damage. 

Top officials in the Biden administration are concerned that, given the context this time is the assassination of a Hamas leader in Tehran rather than an Iranian general in Damascus, it may be more challenging to rally the same international and regional coalition that thwarted the previous Iranian attack.

According to a U.S. official, American intelligence agencies began receiving clear indications last Wednesday that Iran is preparing to respond.

Two senior Pentagon officials stated that it could take several days for Iran and its allies to coordinate and prepare for an attack on Israel.

The Pentagon and U.S. Central Command are making similar preparations to those they took before the April attack, the officials added.