The footage was released following Sinwar's death in the southern Gaza city of Rafah.

The footage shows Sinwar, his wife and children moving belongings, including water, pillows and mattresses, and a television set.

Israeli Army spokesman Rear Admiral Daniel Hagari said the tunnel was located under the family home in Khan Younis.

The footage was recovered from Gaza several months ago during an operation

"Even on the eve before the brutal massacre, Sinwar was busy with his survival and the survival of his family,” Israel Defense Forces (IDF) spokesman Rear Adm. Daniel Hagari said in a press conference where he showed the footage.

"A few hours before the massacre, Sinwar and his family escaped alone to the tunnel...they went back and forth with sacks of food, water, pillows, a plasma television, mattresses and other supplies for a long stay...Hours before the massacre, Sinwar only cared about himself and his family, while he sent terrorists for the murderous attack on Israeli children, women and men," Hagari said.

He showed photos of the underground compound, which had toilets, showers, a kitchen, beds, uniforms, safes, lots of cash, documents and other intel in the tunnel.

The spokesman said that in February, the IDF reached the underground fortress Sinwar had built in Khan Younis, but he had fled shortly before.

Hamas, meanwhile, said Sinwar died heroically engaging in battle, calling Hagar's remarks "blatant lies". Drone footage from earlier this week showed Sinwar critically wounded in his last moments, throwing an object at the drone. An autopsy found that Sinwar was killed by a gunshot to the head.