Between 2010 and 2012 four other nuclear scientist in Iran were assassinated in similar ways.
There is little doubt about who is responsible for this attack:
Fakhrizadeh was named by Israeli Prime Minister Benjamin Netanyahu in 2018 as the director of Iran's nuclear weapons project.When Netanyahu revealed then that Israel had removed from a warehouse in Tehran a vast archive of Iran's own material detailing with its nuclear weapons program, he said: "Remember that name, Fakhrizadeh."
According to the IAEA Iran did not and does not have a nuclear weapons program. More than 20 years back some Iranian scientists did an organizational study about what they would have to do to create a nuclear weapons program. But politics intervened and the program was never launched.