Gaza City is one of the most densely populated areas in the densely populated Gaza Strip.

The city's home now to more than a million people.

Last week, Israel launched a new ground offensive into Gaza City.

Israeli officials say the long-expected operation started early Tuesday and will proceed gradually,

with the expectation of fighting up to 3,000 Hamas militants still believed to be there.

We spoke to one person.

He'd been pulling a cart loaded with all his family's possessions for more than 12 hours,

pushing through these horrendous conditions.

We are seeing an unprecedented humanitarian disaster that could be easily avoided. It's not feasible to move

one million people from Gaza City to the south. Civilians there are faced with a choice.

Stay or go. Either call can be deadly. The incursion could also be deadly for the Israeli

hostages held by Hamas, at least some of whom are believed to be in Gaza City.

So why did Israel make this choice?

Coming up on Today Explained.

Support for this show comes from Isihat.

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