Hamas leader Yahya Sinwar has been silent for months

In a windowless room, somewhere in the bowels of the Israel Defense Forces (IDF) headquarters, Chief of Staff Lt Gen Herzi Halevi jabbed his index finger forward.

Israel had just assassinated the Hezbollah leader and was about to invade Lebanon when he summoned his generals and commanders to take instructions.

But pictures of the meeting released to the press showed a seemingly unrelated image in the background.

Up on a screen mounted on the wood-panelled wall are fourteen mugshots of the Hamas chain of command – most of them with a giant red cross over them to mark that they had been killed.

At the top of the chain was public enemy no 1, Hamas leader Yahya Sinwar, with his grey hair and salt and pepper beard. For the first time since the war began, he had a question mark over his head.

The image set off a fresh round of speculation that Israel’s most wanted, the man who planned and ordered the Oct 7 massacres, was finally dead.

A little over a week until the anniversary of the terror attacks this coming Monday, was it possible the IDF had finally got their man?

Rumours about his possible death had emerged a few weeks earlier when intelligence officials began briefing that one of the precision airstrikes that had levelled Gaza may have killed the leader.

No concrete evidence has emerged since, but the pattern follows similar high-level assassinations in Gaza, which have taken a few weeks to be publicly announced.

Two well-placed Israeli officials told The Telegraph that the defence establishment believes that Sinwar is now dead.

One of the sources said that “it is highly likely that Yahya Sinwar was eliminated in one of the IDF strikes. The assessments in Israel’s security leadership suggest that Sinwar was most likely killed.”

However, plenty of caution remains. Sceptics question the timing around the Oct 7 anniversary and how Israel would have killed a man said to have been hidden deep underground and surrounded, according to reports, by Israeli hostages.

Sinwar could have decided the best way to keep himself safe as assassinations take down his top leaders is to retreat entirely from view. American officials told the New York Times they believed Sinwar is still alive and making key decisions for Hamas.

The clues

Israeli sources told The Telegraph that one piece of evidence emerging about his possible death was an end to communications with the leader.

One source said the handwritten notes delivered by couriers that had been keeping the hostage negotiations alive had dried up.

However, Israel also announced on Thursday it had killed Sinwar’s right-hand man some three months ago. Rawhi Mushtaha was allegedly one of those involved in the complex human chain of delivering the notes.

Israel’s intelligence machine has relied on tracking couriers in the past, notably to find and kill Hamas’ military chief Mohammed Deif, who was killed in an airstrike in Gaza in July. The US adopted a similar technique to find Osama bin Laden.

Sources suggested Israel’s defence establishment is believed to be currently in a situation similar to when an airstrike targeted Mr Deif in Khan Younis on July 13. The official confirmation of his death was announced nearly three weeks later on August 1.

Sinwar was appointed the political leader of Hamas after Ishmail Haniyeh was killed in an alleged Israeli attack in Tehran in July, making him the all-powerful figure of the terror group.

Widely seen as the architect behind the Oct 7 massacre, he is considered the most valuable target for Israel, which refers to him as a “dead man walking.”

Israeli forces have scoured Gaza for Sinwar since they invaded the enclave in late October and even came close to capturing him several times. The IDF assessed early on in the war that the Hamas leader was hiding in southern Gaza, specifically in a tunnel deep underground.

In February, the IDF released the first footage of Sinwar since Oct 7, showing his children and wife walking through a tunnel under a cemetery in the Bani Suheila area in Khan Younis.

Sinwar is seen in flip flops and carrying a bag as he walks through the tunnel behind his family on Oct 10 but Israeli soldiers only reached the tunnel in February where they found the surveillance footage.

IDF spokesperson Daniel Hagari said that the tunnel from which Sinwar escaped before Israeli forces came contained “bedrooms of senior Hamas officials and the office of the commander of the Khan Younis Brigade’s Eastern Battalion, from where he directed the attack on Oct 7”.

Senior Hamas officials resided in the compound in “comfortable conditions” with food and bathrooms, along with safes with “personal funds of millions of shekels and dollars in cash,” Mr Hagari added.

In December, Mr Netanyahu announced that Israeli troops had surrounded Mr Sinwar’s home in Khan Younis.

“I said last night that our forces could reach anywhere in the Gaza Strip. Now, they are encircling Sinwar’s home. His home is not his fortress, and while he may flee, it is only a matter of time until we get him,” Mr Netanyahu said.

In August, the outgoing commander of the IDF’s 98th Division, Brig. Gen. Dan Goldfus, told Channel 12 that the army was “minutes” away from catching the Hamas leader.

“We were close. We were in his compound. We got to an underground compound.  We found a lot of money there. The coffee was still hot. Weapons strewn around,” Mr Goldfus said.

And as Israel continues to kill Hamas commanders, Mr Sinwar is running out of places to hide.

“Every day, he has trouble finding places where he can hide. The list of associates and confidants is being reduced,” a security source told the Jerusalem Post in August.

But Israel is also dealing with a far wider and more complex network of tunnels than they believed existed before the invasion.

That leaves intelligence gathering as the key.

The hunt

Hunters fall under an umbrella of units under the Israeli Security Agency and include intelligence officers, special operation units from the Israel Defense Forces (IDF), military engineers and surveillance experts.

Teams of experts entering the tunnels, like the special section of the Combat Engineering Corps, are armed with ground-penetrating radar.

Yahalom, a special section within the Combat Engineering Corps, has more experience in tunnel warfare than any of its counterparts in Western armies and has access to state-of-the-art US-made ground-penetrating radar.

Many clues have turned up in Hamas compounds revealing everything from the terror group’s plans, orders, maps and blueprints of compound structures.

Seized computers, documents and surveillance footage have all helped keep the trail warm.

“Hundreds and thousands of interrogations of terrorists and senior leaders would not have yielded such intimate intelligence on their methods of order and organisation in such a short period,” a military official said in July.

But the interrogations of thousands of members of Hamas and other terror groups who were arrested since Oct 7 has also helped.

They have so far led to the IDF finding tunnels and weapon depots and revealing hospitals and Red Crescent facilities Hamas allegedly uses to operate from.

“Each and every investigation leads to the incrimination of new sites, and the human intelligence that emerges… is an inseparable layer of the complete intelligence picture,” the IDF said already back in November.

The importance of tracking Sinwar’s communication with other members has also become clear.

Previously Israel’s secretive signals intelligence unit 8200 had been employed to eavesdrop on Hamas communications.

But their role was reduced since Hamas leadership ditched all electronic communication in favour of notes and oral messages delivered by runners.

“Using complex means, he communicates with all the leadership of the movement both inside (Gaza) and outside, and also with the (Ezzedine) al-Qassam Brigades,” a senior Hamas leader told AfP.

“He follows complex security procedures for his personal protection, but this does not prevent him from continuing his duties and making decisions,” he added.

The repercussions

If Mr Sinwar has been killed, it raises a number of questions.

Khaled Meshaal, the former leader of Hamas, is perhaps the only person who could fill his shoes and govern the terror group effectively, albeit from abroad and not inside Gaza.

There is also the possibility that hostages may have been killed in the same strike on Sinwar.

If so, the Israeli government will be met with fury from the vast majority of the public that wants a ceasefire deal with Hamas.

In theory, killing Sinwar could give Mr Netanyahu the win he needs to sign a deal that could end the war and release the remaining hostages.

Khalil al-Hayya, the deputy leader of Hamas, is currently representing the terror group in the negotiations, which notably have been stalled for weeks.

But since he doesn’t have a mandate to strike a deal by himself, there won’t be any ceasefire until Mr Sinwar either shows signs of life, and re-engages with mediators, or he is announced dead and a new leader is appointed.

Giora Eiland, the former head of Israel’s national security council, told The Telegraph that there are definitely “signs” that Sinwar has been killed.

But he added he hasn’t received any information from Israeli officials he’s spoken to in recent weeks.

“It’s still a mystery,” he said.

Mr Netanyahu’s speech on Sunday raised eyebrows as it listed Sinwar alongside other commanders killed by Israel.

“The regime in Tehran does not understand our determination to defend ourselves and to exact a price from our enemies. Sinwar and Deif did not understand this; neither did Nasrallah or Mohsen,” Mr Netanyahu said.

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