Jakarta, CNBC Indonesia - Israeli spies had been in Iranian territory long before launching a wave of nuclear attacks.

Israel's Mossad intelligence agency had smuggled weapons into Iran before the attacks, according to Israeli security officials, and would use the weapons to target Iran's defenses from within.

Quoting CNN International, Sunday (15/6/2025), officials said Israel had established a base to launch explosive drones inside Iran.

The drones were then used to target missile launchers near Tehran. Precision weapons were also smuggled in and used to target surface-to-air missile systems, paving the way for the Israeli Air Force to carry out more than 100 strikes with more than 200 aircraft in the early hours of Friday local time.

The plan to cripple Iran's defenses appears to have worked. Israel said all of its planes returned safely from the first wave of strikes, an apparent demonstration of Israeli air superiority over parts of the country hundreds of miles away.

It is the latest operation to show how deeply Israeli intelligence agencies, including the Mossad, have penetrated some of Iran’s most closely guarded secrets. The operation has made the Mossad seem like a nearly unstoppable force in Iran, capable of attacking some of its highest officials and most sensitive locations.

"Mossad has treated Iran like its playground for years," said Holly Dagres, a senior fellow at the Washington Institute.

"From assassinating top nuclear scientists to sabotaging Iran's nuclear facilities, Israel has proven time and again that it has the upper hand in this shadow war that has now been waged openly since the first retaliatory strike in April 2024."

Israeli security sources said the latest operation required the commandos to operate deep inside Tehran and across the country while avoiding detection by Iran's security and intelligence agencies. The sources said the Mossad team targeted air defense missiles, ballistic missiles and missile launchers as the Israeli Air Force strikes began.

A second Israeli security source said the Mossad operation had been going on for years, involving intelligence gathering efforts and the placement of Mossad commandos deep behind enemy lines.