Israel's latest ground invasion of Gaza City's Shujaiya neighbourhood is expected to last for weeks, according to Israeli media reports.
Despite Israeli forces withdrawing from northern Gaza in January after having claimed to have "dismantled" the Palestinian group's command structure, the army issued evacuation orders on Thursday, saying it was scoping out and destroying Hamas tunnels.
The army says it is eliminating tunnels "that were missed during the first time through" as it did not operate in all parts of the district during its initial invasion. It also says Hamas is regrouping.
A report from Israel's Jerusalem Post said the army would need "years" to dismantle the Gaza tunnel system, adding that the military has not been given enough time for the task.
Israeli tanks have targeted houses in Shujaiya, preventing families from being able to leave, while 60,000 to 80,000 have since been displaced.
The army claims to have killed several fighters and conducted raids over the past 24 hours, while the its air force has targeted alleged Hamas infrastructure sites.
Shujaiya has long been considered to be a hotbed of Palestinian resistance against Israel, with the army taking significant losses in the area in the current conflict and in previous incursions.
Ten Israeli soldiers were killed in a series of ambushes by fighters from Hamas's Al-Qassam Brigade, giving it a reputation as a "deathtrap" for Israeli forces.
The neighbourhood is at the site of the Tell Al-Muntar hill, which has historically been known to give the area a military advantage due to its commanding views and strategic access to the whole of Gaza City.
Since mid-March, Israeli forces have conducted four re-invasions in northern and central Gaza, including Al-Shifa Hospital, Jabalia, and Nuseirat – all under the pretext of destroying Hamas.
The army has also pushed deeper into western and central Rafah in the south, which was meant to be considered a "safe zone" for Palestinians escaping the north.