Brigadier General Esmail Qa’ani issued the warning in a letter sent on Sunday to Ismail Haniyeh, head of Hamas’ political bureau.
Qa’ani extended congratulations and condolences to Haniyeh over the martyrdom of Arouri in a terrorist Israeli drone strike in Lebanon.
“The world will witness how the comrades of Martyr Arouri turn into the nightmare of the child-killing regime,” he wrote.
“Arouri was martyred with a brilliant record in the first, al-Aqsa and al-Quds intifadas,” the IRGC commander added, referring to three Palestinian uprisings against the Israeli regime over the past years.
Arouri, 57, was assassinated in Beirut’s southern suburb of Dahiyeh on January 2.
He was one of the founders of Hamas’ military wing, known as Qassam Brigades, before taking on a political portfolio in recent years.
He was seen as a key player in the movement, masterminding its operations in the West Bank from exile in Syria, Turkey, Qatar and finally Lebanon after long stints in Israeli prisons.
Haniyeh said the cowardly assassination of Arouri proved Israel is seeking to evade defeat and cover up its failure in its ongoing genocidal war on the besieged Gaza Strip.