Israel made its first statement of a change from an air war to ground operations to root out Hamas rebels a week after their deadly rampage in southern Israel on Friday, claiming that its soldiers and tanks had conducted incursions inside the Gaza Strip.

After Israel ordered more than a million Palestinians to leave the northern part of the Gaza Strip within 24 hours, some inhabitants of Gaza were fleeing their houses on Friday to avoid an Israeli assault. Hamas warned them against going.

Israeli military spokesperson Rear Admiral Daniel Hagari said troops backed by tanks had mounted raids to attack Palestinian rocket crews and seek information on the location of hostages taken by Hamas.

Several thousand residents could be seen on roads heading out of the northern part of the Gaza strip, but it was impossible to tell their numbers. Many others said they would not go.

Hamas, which controls the densely populated Palestinian territory, vowed to fight until the last drop of blood. The Israeli military said a significant number of Gazans had begun moving southwards “to save themselves”.

“Death is better than leaving,” said Mohammad, 20, standing in the street outside a building reduced to rubble in an Israeli air strike two days ago near the centre of Gaza.

“I was born here, and I will die here, leaving is a stigma.”

Mosques broadcast the message: “Hold on to your homes. Hold on to your land”.

“We tell the people of northern Gaza and from Gaza City, stay put in your homes, and your places,” Eyad Al-Bozom, spokesman for the Hamas Interior Ministry, told a news conference.