ISRAEL’S military has ordered the evacuation of a crowded part of Gaza designated as a humanitarian zone, saying it is planning an operation against Hamas militants in Khan Younis.

It includes parts of Muwasi, a makeshift tent camp where thousands of people were seeking refuge.

The order comes in response to rocket fire which Israel says originates from the area.

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It is the second evacuation issued in a week in an area designated for Palestinians fleeing other parts of Gaza.

Many Palestinians have been uprooted multiple times in search of safety during Israel’s punishing air and ground campaign.

On Monday, after the evacuation order, several Israeli airstrikes hit around Khan Younis, killing at least 70 people, according to Gaza’s health ministry, citing figures from Nasser Hospital.

The area is part of a 20 square mile “humanitarian zone” to which Israel has been telling Palestinians to flee throughout the war.

Much of the area is blanketed with tent camps that lack sanitation and medical facilities and have limited access to aid, United Nations and humanitarian groups say.

About 1.8 million Palestinians are sheltering there, according to Israel’s estimates. That is more than half Gaza’s pre-war population of 2.3m.

Israel's bombardment of Gaza has killed more than 39,100 Palestinians, according to the territory’s health ministry, which does not distinguish between combatants and civilians in its count.

Smoke rises after Israeli bombardments in Khan Younis, Gaza StripSmoke rises after Israeli bombardments in Khan Younis, Gaza Strip (Image: Abdel Kareem Hana/AP)

The UN estimated in February that some 17,000 children in the territory are now unaccompanied, and the number is likely to have grown since.

About 115 are still in Gaza, about a third of them believed to be dead, according to Israeli authorities.