Hossein Amir-Abdollahian, special assistant to the speaker of Iran’s Parliament, made the remarks in an exclusive interview with Arabic-language Al-Alam television news network on Tuesday.
"The perpetrators of this assassination, some of whom have been identified and even arrested by our security apparatus, will not escape justice and will be dealt with severely," Amir-Abdollahian told the news network, according to Press TV.
The Iranian official also underlined that Israeli regime was involved in the terrorist act but said it rulers were unable to accomplish the plot without the help of others, including the US spy agency.
"Regarding the assassins and organizers of the assassination, there is various evidence that the Zionists were involved in this issue, but whether the Zionists were able to do it alone and without complicity of the US spy agency or other agencies, they certainly could not do it," Amir-Abdollahian said.
Fakhrizadeh was targeted in a multi-pronged terrorist attack in Absard town of Tehran province’s Damavand County on November 27.
Iranian government officials and military commanders have hinted that the Israeli regime, which has already murdered a number of Iran's scientific elites, was behind the recent terror attack, vowing harsh revenge against all the criminals involved.
Iran’s President Hassan Rouhani has said the assassination by "Zionist elements" was a grave and inhumane crime aimed at curbing the Iranian march toward scientific progress.