CNN  — 

Israel has targeted Hamas leader Mohammad Sinwar in a strike on a hospital in southern Gaza on Tuesday evening, according to a senior Israeli official and two sources familiar with the matter.

He became the militant group’s de facto leader after the Israeli military killed his brother, Yahya Sinwar, last October.

The Israel Defense Forces (IDF) said it carried out a strike on the European hospital in Khan Younis, targeting “Hamas terrorists in a command and control center” in underground infrastructure beneath the hospital. The IDF did not identify the target of the strike.

Multiple airstrikes hit the yard of the hospital, according to Dr. Saleh Al Hams, the head of nursing. Some people are buried under the rubble, he said, calling it “a catastrophe.” Medical teams tried to move patients to safe units inside the hospital.

Video from the scene showed towering pillars of smoke and dust from what appeared to be some of the largest strikes in Gaza in recent weeks.

The targeting of Sinwar comes one day after Hamas released Israeli American Edan Alexander in what was a goodwill gesture to the United States. The deal for a single hostage’s release sidelined Israel, as Hamas communicated with the Trump administration.

The US expressed some optimism about negotiations set to take place in Qatar with President Donald Trump and his envoy Steve Witkoff in the Middle East. Before leaving Israel, Witkoff promised the families of the hostages that he “will be relentless on that pursuit.”

But with negotiations about to start in Doha – and with an Israeli team en route – the targeting of Sinwar means Israel has just attempted to kill Hamas’ key decision maker needed to seal any potential agreement.

Israeli officials considered Mohammad Sinwar just as hardline as his brother, Yahya, but much more experienced militarily. According to the IDF, he commanded the Khan Younis Brigade until 2016. Like Yahya, he is believed to be one of the main planners of the October 7 terror attack on Israel.

Since the start of the war, he has remained hidden, along with many of Hamas’ senior leaders in Gaza. In December 2023, the IDF released video of what they said was Mohammad Sinwar driving through a tunnel in Gaza. In February 2024, the IDF said they had located his office in western Khan Younis.

Former US Ambassador to Israel Dan Shapiro said Sinwar was likely an obstacle in negotiations. “There is little chance the war can end before he dies,” Shapiro, a senior fellow at the Atlantic Council, told CNN. “His removal could open the door for the release of all hostages and beginning to move toward a post-war future for Gaza without Hamas.”

This is a developing story and will be updated.