The Israel Defense Forces and the country's Shin Bet domestic intelligence agency have announced they are investigating whether Hamas terror chief Yahya Sinwar was killed in the Gaza Strip on Thursday.

Authorities said in a joint statement that “three terrorists were eliminated during IDF operations in the Gaza Strip” and that “the possibility that one of the terrorists was Yahya Sinwar is being examined.”

“In the building where the terrorists were eliminated, there were no signs of the presence of hostages in the area,” they added. “The emergency services on site continue to act with due caution.”

Nicknamed the “Butcher of Khan Younis” by Israel for his violent and cruel torture methods against its enemies, both Israelis and Palestinians, Sinwar, 60, is widely considered to be responsible for the massacre of Israeli civilians on October 17 was carried out by thousands of Hamas fighters. 7.

Hamas appoints YAHYA SINWAR, MASTERMIND OF OCTOBER. 7 ATTACKS, AS A NEW LEADER

Yahya Sinwar chairs a meeting with leaders of Palestinian factions at his office in Gaza City on April 13, 2022. (AP)

Israel Defense Forces spokesman Lt. Col. Richard Hecht told reporters last October that “Sinwar is the leader of Hamas in Gaza and a dead man is on the way.”

“We will get there no matter how long it takes… and this war could be protracted,” he said.

Sinwar was believed to be somewhere in the Palestinian enclave but hidden deep underground in the labyrinth of tunnels that Hamas uses to transport weapons and fighters and where it may even be holding hostages. Sinwar was born in the Khan Younis refugee camp when the area was still part of Egypt.

According to several sources, he has always been a militant activist and joined Hamas shortly after its founding in 1987. Two years later, he was arrested by Israel for his involvement in the kidnapping and killing of two Israelis and the torture and murder of four Palestinians he believed to be collaborators.

Israel's hunt for Hamas terror leader Yahya Sinwar: “Dead man on the run”

Israel Defense Forces Lt. Gen. Herzi Halevi (left) and Shin Bet leader Ronen Bar conduct a situation assessment on Thursday, Oct. 17. (IDF)

Sinwar was sentenced to life in prison, eventually served 22 years in an Israeli prison, and was eventually released as part of a prisoner swap for kidnapped Israeli soldier Gilad Shalit in 2011.

“Sinwar has been active since the beginning of Hamas,” Kobi Michael, a senior researcher at the Institute for National Security Studies in Tel Aviv, previously told Fox News Digital. “In prison, he became a prominent leader of the Hamas prisoners and was a very influential figure among all Palestinian prisoners.”

After being returned to Gaza as part of the Shalit Agreement, Sinwar became a popular leader of Hamas, an offshoot of the Muslim Brotherhood, and was elected in a secret vote in 2017 to replace incumbent political leader Ismail Haniyeh, who was killed in Iran was this July.

Yahya Sinwar appears during a ceremony for Hamas fighters killed by Israeli airstrikes at the Yarmouk football stadium in Gaza City in May 2021. (Laurent Van der Stockt/Getty Images)

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After Haniyeh's death Sinwar was named the new leader of Hamas.