As the months went on, Israeli officials repeatedly said they had got close to him.
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.
He said: “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.”
With little information emerging about him, rumours that he was already dead also swirled.
Speculation had heightened recently when it was noticed that a recent government picture of a high-level military meeting showed a Hamas organisational chart, with a question mark over Sinwar’s head.
But American officials earlier this month said that while his communications had gone quiet, there was no evidence he was dead and instead they thought he was alive and still making decisions.
Their assessment of the fugitive was that he was isolated and hiding in Gaza.