Katz Israel, the Israeli defense minister, said on Monday that his country would "firmly" enforce the ceasefires that have paused fighting in Gaza.
"Anyone who violates the rules or threatens IDF forces will bear the full cost," he said in Hebrew on social media. "We will not allow a return to the reality of Oct. 7."
Tens of thousands of people were marching and driving on Monday back to northern Gaza, after Israel allowed them to cross into the north for the first time in over a year.
Long lines of Palestinians -- some singing, others smiling and some kneeling to kiss the soil as they stepped into the northern part of the strip -- were seen making their way home.
Those returning home were moving along two main routes.
Many of those who were were walking home were moving along al-Rashid Street, a path expected to be taken by about 300,000 people.
Many of those who were driving north were doing so along Salah al-Din Road.
A line of cars could be seen stretching for about 8 miles on Monday morning, as they waited for permission to cross into the northern part of Gaza.
-ABC News’ Sami Zyara, Diaa Ostaz, Jordana Miller, Nasser Atta and Samayeh Malekian
The Palestinian Red Crescent Society said its team evacuated one person who was killed, and four people who were injured, after an attack by Israeli snipers near the Wadi Gaza Bridge on Sunday.
Israel Defense Forces said in a statement that troops fired "warning shots" at "several gatherings of dozens of suspects" who the IDF said posed a threat to them.
Additionally, a rocket was destroyed by Israeli troops in southern Gaza, according to the IDF's statement.
Newly confirmed Secretary of Defense Pete Hegseth had an introductory call on Sunday with Israeli Prime Minister Benjamin Netanyahu, according to a statement from a U.S. senior defense official.
"Both leaders discussed the importance of advancing mutual security interests and priorities, especially in the face of persistent threats," according to the statement.
Hegseth, who won Senate confirmation after being selected by President Donald Trump for the role, stressed to Netanyahu that the U.S. is "fully committed" to ensuring that Israel "has the capabilities it needs to defend itself," according to the statement.
Additionally, the defense official said that "both leaders agreed to remain in close contact."