Who was Hamas leader and Oct 7 mastermind Yahya Sinwar killed by IDF

The

Israel

Defence Forces on Thursday killed the "mass murderer" and

October 7

mastermind Yahya Sinwar, as confirmed by the Israeli foreign minster Israel Katz.
"The mass murderer Yahya Sinwar, responsible for the massacre and atrocities of October 7th, was eliminated today by

IDF

(Israeli military) soldiers," he said in a statement.
It remains uncertain who would succeed Sinwar and how that change might impact the cease-fire efforts, which stalled in August following months of negotiations facilitated by the United States, Egypt, and Qatar.

Mastermind of Oct 7 attack

Sinwar, alongside Mohammed Deif, the head of

Hamas

' armed wing, is thought to have planned the surprise attack on Israel on October 7. This assault resulted in the deaths of approximately 1,200 Israelis, predominantly civilians, and ignited a conflict that has claimed the lives of over 42,000 Palestinians in Gaza, according to local health authorities.

Hamas has stated that the attack was launched in retaliation for Israel's treatment of Palestinians and aimed to bring international attention back to the Palestinian cause.
In May, the prosecutor of the International Criminal Court sought arrest warrants for Sinwar, Deif, and Ismail Haniyeh due to their alleged involvement in the attack. While Israel claimed to have killed Deif in a strike in July, Hamas maintains that he is still alive.

'The Butcher of Khan Younis'

Sinwar was born in 1962 in a refugee camp in Khan Younis, Gaza. He became an early member of Hamas, established in 1987, and later led the group's security arm, which focused on eliminating informants for Israel.
In the late 1980s, Israel arrested him, during which he admitted to killing 12 suspected collaborators. This led to his nickname, “The Butcher of Khan Younis.” He received a sentence of four life terms for various offenses, including the murders of two Israeli soldiers.

'Prison builds you'

Sinwar once expressed to an Italian journalist that prison serves as a crucible for personal growth. "Prison builds you," he stated, emphasizing that it allowed him time to reflect on his beliefs and the sacrifices he was willing to make for them, NYT reported.
Despite this, Sinwar attempted to escape from custody multiple times, including digging a tunnel in his cell to break out through the visitor center. He also found ways to coordinate with Hamas leaders outside, successfully smuggling cellphones into the prison and using lawyers and visitors to send messages, including plans to kidnap Israeli soldiers in exchange for Palestinian prisoners.

Sinwar's Gaza saga

Sinwar swiftly climbed the ranks of Hamas leadership, earning a reputation for ruthlessness. He is widely believed to have orchestrated the 2016 assassination of another senior Hamas commander, Mahmoud Ishtewi, amid an internal power struggle.
As the head of Hamas in Gaza, Sinwar effectively gained control over the territory and collaborated with Haniyeh to strengthen the group's ties with Iran and its regional proxies, while also enhancing Hamas's military capabilities.