Israeli Defense Forces announced that Mr Safieddine, cousin of Mr Nasrallah, and other top-ranking Hezbollah officials were killed in an attack.
Mr Sinwar was designated a terrorist by the EU. In January, the European Union declared him a wanted terrorist for masterminding the October 7 attacks that killed over 1,000.
Israel launched a fresh series of attacks on the Lebanese capital of Beirut on Wednesday.
Iran has extended the closure of its airspace as it expects Israeli retaliation following its attack on the enemy country on Tuesday evening.
Mr Netanyahu has vowed that Israel would retaliate against Iran’s missile attack, during which 180 missiles were fired toward Israel.
“But if the Zionist regime takes retaliatory action, our response will be even tougher,” the minister said, referring to possible Israeli retaliation.
The attack was said to have been a response to the killing of Hezbollah leader Hassan Nasrallah and others.
He joined Hamas in the 1980s and has been the leader of the group in Gaza since 2017.
Mr Haniyeh called on Arab and Islamic countries to form a popular front to end Israeli aggression.
Malaysia has long supported the Palestinian cause, with Prime Minister Anwar Ibrahim saying he did not agree with Western pressure to condemn Hamas.
