The Israel Defense Forces said in a press briefing early on Tuesday that its forces had taken "operational control" of the Palestinian side of Gaza's border crossing with Egypt.
The IDF's 401st tank brigade entered the Rafah crossing early on Tuesday, it said.
It said special forces were scanning the area and had been operating there since the previous night, particularly in an area in eastern Rafah.
"Right now, we have special forces scanning the crossing ... We have operational control of the area and other crossings, and we have special forces scanning the area," the military said.
It added that currently engaged in a "very targeted operation and a very limited scope against very specific targets" in eastern Rafah.
The military also said that the Kerem Shalom crossing from Israel into Gaza was temporarily closed as well early on Tuesday, citing security reasons. It said it would reopen when the security situation allowed.
The IDF published video footage, with film taken from on board a single tank showing that tank approaching the crossing. No people or other military vehicles were visible in the shot.
Late on Monday, Israel's military had already said it was carrying out "targeted strikes" in Rafah, reporting the deaths of 20 Hamas militants and the discovery of three tunnels during the operation.
The military said Tuesday that a "vast amount" of people in areas given evacuation notices yesterday "moved to a safer zone."
Rafah — main aid entry point into Gaza, refuge for many
Rafah is a city in southern Gaza that borders Egypt.
In the first months of the conflict, with much of the fighting in northern Gaza, it became a haven for people trying to flee. Usually home to more like 200,000 people, more than a million — or around half Gaza's population — are estimated to have fled there since the war began after the Hamas terror attacks on October 7.
Rafah is also the busiest entry point for humanitarian aid going into Gaza.
Israel had at one point urged Palestinians trying to avoid fighting to the north in places like Gaza City to head for Rafah.
But for months now, Israel's government has been warning of an impending military operation there, which has come in tandem with international calls for restraint and a light touch and warnings of dire consequences in the case of a larger operation.
On Monday, the IDF instead called on people in Rafah to head north towards Khan Younis, saying soldiers would soon be operating in the southern city.
This followed a mortar attack that Israel said hailed from near the border crossing and killed four IDF soldiers.
First reports of IDF activity at Rafah crossing
Israeli Army Radio and Palestinian and Egyptian officials both reported a military presence on the Palestinian side of the Rafah border crossing between southern Gaza and Israel early on Tuesday.
A spokesperson for the Gaza border authority told Reuters that the crossing had been closed amid the presence of Israeli tanks. Reuters also cited humanitarian aid workers as saying deliveries were halted.
Israel had on Monday asked people to leave the area, thought to be a temporary home to more than a million fleeing the fighting in Gaza after a mortar attack that it said hailed from the town killed four Israeli soldiers.
Soon after that, Hamas said it had accepted a cease-fire deal after days of delay. But as celebrations started breaking out in Rafah and elsewhere, Israel's government then responded by saying the deal did not meet its "core demands."
Talks on a possible truce continue on Tuesday. French and Chinese presidents Emmanuel Macron and Xi Jinping, in the south of France for a second day of talks, issued an early statement urging a breakthrough.
The threat of some kind of military operation at Rafah, plus international appeals for restraint from Israel, has been openly in play for months now, albeit without major military activity.
UN agency says currently has no access to Rafah crossing
A spokesman for the UN's humanitarian OCHA agency told reporters in Geneva on Tuesday that the group did not have access to the closed Rafah crossing between Gaza and Egypt.
"We currently do not have any physical presence at the Rafah crossing as our access ... has been denied by COGAT," Jens Laerke said, using the acronym for the Israeli government agency that oversees supplies into the Palestinian territories.
Israel has said that another border crossing at Kerem Shalom was also closed but that it would reopen once the security situation allows. It described the operation in Rafah as having a "very limited scope."
The Office for the Coordination of Humanitarian Affairs, or OCHA, had on Monday warned that Israel's "evacuation orders for East Rafah will only exacerbate civilians' suffering."
It also noted on Monday the importance of the Rafah crossing for its own operations.
"Until now, all fuel entering Gaza comes through the Rafah crossing. Any disruption of this fuel supply would halt our humanitarian work," it said.
Egypt condemns 'dangerous escalation' in Rafah
Egypt's Foreign Ministry on Tuesday issued a statement criticizing the Israeli military operations on the Palestinian side of its border crossing with Gaza.
The ministry said the operations constituted a "dangerous escalation threatening the lives of more than a million Palestinians who depend mainly on this crossing as it is the main lifeline of the Gaza Strip."
Cairo warned that the operations could endanger ongoing negotiations, which Egypt is helping to broker, seeking a cease-fire and hostage-release deal.
"The Arab Republic of Egypt calls on the Israeli side to exercise the utmost levels of restraint and to avoid a policy of brinkmanship that has a long-term impact and that would threaten the fate of the strenuous efforts made to reach a sustainable truce inside the Gaza Strip," the Foreign Ministry said.
It said it would call on international partners to try to intervene and exert what diplomatic influence or pressure they could.
