How Khamenei was killed

Nearly all the traffic cameras in Tehran had been hacked for years. And when the senior Iranian officials came to work near Pasteur Street in Tehran - where Ayatollah Ali Khamenei was killed in a US-Israeli air strike on Saturday - the Israelis were watching, according to a Financial Times report.

One camera had an angle that proved particularly beneficial, the British daily said, providing Israel a window into the workings of a monotonous part of the closely guarded compound.

Sophisticated algorithms added details to dossiers on members of these security guards that included their addresses, hours of duty, routes they took to work and, most importantly, who they were usually assigned to protect and transport - building what intelligence officers call a “pattern of life”, the report detailed.

The effort was a part of a years-long intelligence campaign that helped pave the way for the 86-year-old Ayatollah’s assassination.

Tracking this real-time traffic data was one of the many ways Israel and the CIA were able to determine exactly what time the supreme leader would be in his offices on Saturday morning and those who would be joining him.

Israeli intelligence detected a meeting at the leadership compound in the heart of Tehran on Saturday morning and the strikes were moved forward, Reuters had earlier reported.

Crucially, the CIA learned that the supreme leader, who subjected Iranians to severe authoritarianism and repression, would be at the site.

Israel was also able to disrupt single components of roughly a dozen or so mobile phone towers near Pasteur Street, the report said, making the phones seem as if they were busy when called and stopping Khamenei’s protection detail from receiving possible warnings.

“The intelligence picture of the arch-enemy’s capital was the result of laborious data collection, made possible by Israel’s sophisticated signals intelligence Unit 8200, the human assets recruited by its foreign intelligence agency Mossad and the mountains of data digested by military intelligence into daily briefs,” the report said.

Israel, the report said, used a mathematical method known as social network analysis to parse billions of data points.

“We took their eyes first,” the report said, quoting an intelligence official. Both in the June war and now, Israeli pilots have used a specific kind of missile called the Sparrow, variants of which are able to hit a target as small as a dining table from more than 1,000km away - far from Iran and the reach of any of its aerial defence systems, the report elaborated.

Khamenei, unlike his ally Hezbollah leader Hassan Nasrallah, did not live in hiding. When the CIA and Israel determined that Khamenei would be holding a meeting on Saturday morning at his offices near Pasteur Street, the chance to kill him, along with much of Iran’s senior leadership, was real.

While Donald Trump had repeatedly threatened to attack Iran in recent weeks, building up an “armada” off its shores, negotiations between the US and Iran over the Islamic republic’s nuclear programme were meant to continue this week.

Israeli intelligence had information from signals intelligence, such as the hacked traffic cameras and deeply penetrated mobile phone networks, the report said. The meeting with Khamenei was on schedule, with senior officials heading to the location, the report said. But the Americans had something even more concrete - a human source, the report said. The vital information provided a window of opportunity for the two countries to go in for the kill. And they did.