Thousands of protestors took to the streets of Istanbul late on Wednesday to denounce the killing of Palestinian resistance group Hamas’ leader Ismail Haniyeh.

Haniyeh was assassinated in the Iranian capital Tehran in an attack that drew threats of revenge on Israel and fuelled further concern that the conflict in Gaza was turning into a wider Middle East war.

The demonstrators held posters with Haniyeh's photos and banners reading, "Martyr Haniyeh, Jerusalem is our cause and your path is our path."

Protesters were chanting "murderer Israel, get out of Palestine," "thousands of greetings from Istanbul to the resistance in Gaza" and waving Turkish and Palestinian flags during the march in the Fatih district of Istanbul.

On Wednesday morning, Hamas and Iran announced the assassination of Haniyeh in an Israeli airstrike targeting his residence in Tehran, a day after he attended the inauguration of Iranian President Masoud Pezeshkian.

Though Israel has remained silent about Haniyeh's death, Prime Minister Benjamin Netanyahu has hinted at Tel Aviv's involvement in his assassination.

Israel, flouting a U.N. Security Council resolution demanding an immediate cease-fire, has faced international condemnation amid its continued brutal offensive on Gaza since an Oct. 7, 2023 attack by the Palestinian resistance group Hamas.

At least 39,445 Palestinians have since been killed, mostly women and children, and over 91,000 injured, according to local health authorities.

Nearly 10 months into the Israeli war, vast tracts of Gaza lie in ruins amid a crippling blockade of food, clean water and medicine.

Haniyeh, normally based in Qatar, had been the face of Hamas's international diplomacy as Israel has waged war on Gaza. He had been taking part in internationally brokered indirect talks on reaching a cease-fire in the Palestinian enclave.

Earlier on Wednesday, President Recep Tayyip Erdoğan condemned the assassination in Tehran and said the killing would not break Palestinians' will.