https://www.aa.com.tr/en/middle-east/fakhrizadeh-s-killing-gave-impetus-to-iran-s-nuclear-program/2432077
Fakhrizadeh, who headed the research and innovation wing at Iran's defense ministry, was a shadowy figure who deliberately maintained a low profile owing to a high threat level. He rarely made a public appearance and had only a few sketchy images available publicly.

Now, his life-size portraits greet visitors at the shrine complex in north Tehran where he lies next to another slain nuclear scientist, Majid Shahriari, who was killed Nov. 29, 2010. His 11th death anniversary is being observed Monday, two days after Fakhrizadeh.

At least five senior Iranian nuclear scientists have been killed in targeted attacks since 2010 -- Masoud Ali Mohammadi, Majid Shahriari, Darious Rezaeinejad, Mostafa Roshan and Mohsen Fakhrizadeh.

Fereydoon Abbas, another senior nuclear scientist who later went on to become the nuclear agency chief, escaped an assassination bid the day Shahriari was killed.

Fakhrizadeh's murder, however, marked a "watershed moment" as it pushed Iran to "adopt a more assertive posture" and announce "unprecedented measures" to accelerate its nuclear program, said Hadi GolMohammadi, a political and security observer.
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A year since Fakhrizadeh's assassination, Iran is enriching uranium at 60% purity, much beyond the 3.67% threshold stipulated under the 2015 nuclear deal. It has amassed 25 kilograms (55 pounds) of uranium enriched to 60% and over 210 kilograms (463 pounds) of 20% enriched uranium.

At the time of his killing last November, Iran was enriching uranium at 4.5%, slightly higher than the threshold. Three weeks after the murder, Iran informed the UN nuclear watchdog of its plan to scale up enrichment up to 20% purity.

In April, in response to sabotage at the Natanz nuclear facility, which Iran again blamed on Israel, the level of enrichment surged to 60% purity, which incidentally coincided with nuclear deal talks between Iran and world powers in Vienna.