"The cancerous growth Israel will soon disappear," Iran's Revolutionary Guards Corps commander Muhammad Ali Jafari wrote to Hizbullah leader Sheikh Hassan Nasrallah, the FARS news agency reported Monday. In a letter of condolence following last week's assassination of Hizbullah terror chief Imad Mughniyeh, Jafari said: "I am convinced that with every passing day Hizbullah's might is increasing and in the near future, we will witness the disappearance of this cancerous growth Israel by means of the Hizbullah fighters' radiation [therapy]." In the letter, in which Jafari consoled Nasrallah over the death of the "martyr," he continued: "There's no doubt that the death of this loyal fighter will strengthen the resolve of all revolutionary Muslims and fighters in the struggle against the Zionist regime, particularly the resolve of those who fought by this martyr's side." Mughniyeh was considered to be closely affiliated to the Revolutionary Guards and the al-Quds Brigades. Together, the two organizations trained Hizbullah fighters in Lebanon and Iran and planned terror attacks the world over. Meanwhile, the Kuwaiti newspaper A-Rai quoted officials close to Hizbullah as saying that the group would not rush to avenge Mughniyeh's death, but that it intended to target Israeli figures of a similar rank to the terrorist, who was the group's chief of staff. The newspaper noted that after the killing of former Hizbullah head Abbas Musawi, the organization retaliated years later against Israeli and Jewish targets in Buenos Aires. A-Rai also reported that Mughniyeh had prepared a list of Israeli assassination targets following the Second Lebanon War, when Israel announced its intention to assassinate Nasrallah. Also predicting a future attack, the editor of the Hizbullah-affiliated Al-Akhbar newspaper, Ibrahim al-Amin, said that it was clear Israel was behind Mughniyeh's assassination and that there was an ongoing investigation to determine who had joined the US and Israel in its war against the resistance in Lebanon, Palestine and Iraq. Amin, who is considered a close associate of the group, said that anyone who is interested should join the battle for Israel's destruction and that the tools used in the campaign would be different to those used in the past. He said that Israel should "expect a painful and rational response from an unexpected direction, since the enemy broke all the rules." Threats from Iran and the Muslim world are nothing new. Iran's President Mahmoud Ahmadinejad has called for the destruction of Israel multiple times. Speaking in late January, he repeated his warning. "The lifetime of criminals and invaders [Israel] is over," Iranian state media reported Ahmadinejad as saying while discussing Israeli-Palestinian conflicts in the Gaza Strip. "Powerful hands of Palestinians and regional nations will hit the last blow of destruction against the criminals." Contradicting Amin and the others blaming Israel for Mughniyeh's death, US Director of National Intelligence Mike McConnell said on Sunday that internal Hizbullah groups or Syria may be to blame for the killing of the top Hizbullah commander in Damascus. McConnell said he considered the threat of retaliation for the assassination to be primarily against Israel. But he said US intelligence officials were keeping a close watch and taking any necessary action to protect the United States, as Mughniyeh was "responsible for more deaths of Americans and Israelis than any other terrorist, with the exception of Osama bin Laden." "It is a serious threat," McConnell said. "There's some evidence that it may have been internal Hizbullah. It may have been Syria. "We don't know yet, and we're trying to sort that out." On Sunday night, a special forum convened in Jerusalem to discuss the threat by Hizbullah to perpetrate attacks against Israeli and Jewish targets around the world. The forum included Cabinet Secretary Oved Yehezkel and Jewish Agency Chairman Ze'ev Bielski, as well as senior Foreign Ministry and Defense Ministry officials.