The Israeli army has ordered a mass evacuation of Palestinians from the eastern half of Khan Younis.

Monday’s order is a sign that Israeli troops could soon return to the southern city – the second-largest in Gaza.

Israel ended an offensive in Khan Younis earlier this year and withdrew most of its forces.

Much of Khan Younis was already destroyed in a long assault earlier this year, but large numbers of Palestinians have since moved back in to escape another Israeli offensive in Gaza’s southern-most city, Rafah.

Monday’s evacuation call covered the entire eastern half of Khan Younis and a large swathe of the Gaza Strip’s southeast corner. Earlier in the day, the army said a barrage of rockets out of Gaza was fired from Khan Younis.

An evacuation and eruption of fighting in the Khan Younis area could further hamper Palestinians’ access to much-needed potable water.

Included in the evacuation zone is a water line that Israel installed following criticism over its cutoff of water to the strip early in its campaign.

Displaced Palestinian children fill plastic bottles with water as others wait their turn at a makeshift tent camp in Khan Younis
Displaced Palestinian children fill plastic bottles with water as others wait their turn at a makeshift tent camp in Khan Younis (Jehad Alshrafi/AP)

Also in the zone is the area surrounding the Kerem Shalom crossing, the major aid crossing to southern Gaza, as well as an aid route that Israel said it would safeguard to allow trucks carrying humanitarian aid to enter the strip.

Very little aid has entered the strip due to lawlessness along the aid route, and a new offensive would risk further harming aid efforts.

The evacuation order indicates that Hamas has regrouped in the area.

Israel has said it is in the final stages of an offensive in nearby Rafah, and there has been heavy fighting in recent days in parts of Gaza City in the north.

Earlier on Monday, Israel released 55 Palestinians whom it had detained from Gaza, including the director of the territory’s main hospital, Mohammed Abu Selmia, who was freed without charge or trial after being detained in November when Israeli forces raided Shifa Hospital.

Video grab of Mohammed Abu Selmia with two family members after his release by Israel
Mohammed Abu Selmia, the director of Gaza’s main hospital, who was detained by Israeli forces in November, sitting with family members after his release on Monday (Mohammad Jahjouh/AP)

In video comments aired by Palestinian media following his release, Mr Abu Selmia accused Israeli authorities of subjecting Palestinian detainees to “daily physical and psychological humiliation”. Israeli authorities have denied such allegations.

Israel launched the war after Hamas’s October 7 attack, in which militants stormed into southern Israel, killed some 1,200 people — mostly civilians — and abducted about 250.

Since then, Israeli ground offensives and bombardments have killed more than 37,700 people in Gaza, according to the territory’s Health Ministry, which does not distinguish between combatants and civilians in its count.

The war has largely cut off the flow of food, medicine and basic goods to Gaza, and people there are now totally dependent on aid.

The top United Nations court has concluded there is a “plausible risk of genocide” in Gaza — a charge Israel strongly denies.

Palestinians walk through a street market in Khan Younis
Palestinians walk through a street market in Khan Younis (Jehad Alshrafi/AP)

Most of Gaza’s population of 2.3 million have fled their homes, with many displaced multiple times. Israeli restrictions, fighting and the breakdown of public order have hindered the delivery of humanitarian aid, fuelling widespread hunger and sparking fears of famine.

UN secretary-general Antonio Guterres said the new evacuation order “just shows yet again that no place is safe in Gaza” for Palestinian civilians.

“It’s another stop in this deadly circular movement that the population in Gaza has to undergo on a regular basis,” he said in a statement calling for a ceasefire.

Also on Monday, victims of Hamas’s October 7 attack sued Iran, Syria and North Korea, saying their governments supplied the militants with money, weapons and know-how needed to carry out the assault that precipitated Israel’s ongoing war in Gaza.

The lawsuit, filed in federal court in New York, seeks at least four billion dollars (£3.16 billion) in damages for “a co-ordination of extrajudicial killings, hostage takings, and related horrors for which the defendants provided material support and resources”.

Iran’s mission to the United Nations declined to comment on the allegations, while Syria and North Korea did not respond.

Later on Monday the Israeli military said a soldier had been killed by a roadside explosion in the northern West Bank.

Israeli media say the explosion took place in Nur Shams – the urban refugee camp near the city of Tulkarem where the army has been operating in recent days.

Earlier on Monday the army announced the death of another soldier killed in fighting in the southern Gaza Strip.

More than 600 Israeli soldiers have been killed since the war against Hamas erupted on October 7.