The Israeli Defense Forces (IDF) said on social media that it "resumed combat" minutes after the truce with Hamas in the Gaza Strip expired at 7 a.m. local time (0500 GMT).
"The IDF has resumed combat against the Hamas terrorist organization in the Gaza Strip," the Israeli military said.
The pause in fighting saw the release of hostages held by Hamas in Gaza as well as Palestinians detained in Israeli prisons. Israel's military said early on Friday that its defense systems had intercepted a projectile launched from Gaza after air raid sirens went off near the border.
"Following sirens that sounded in communities near Gaza, the IDF Aerial Defense Array successfully intercepted a launch from Gaza," the Israel Defense Force (IDF) military said on social media.
There was no immediate comment from the militant group Hamas about the incident. But the IDF's comments came as the deadline to extend the truce between Israel and Hamas once again loomed.
Israel's Kan public broadcaster said it was the first time air raid sirens had sounded near the border to Gaza since the truce started on November 24. Nominally, the truce is set to expire at 7 a.m. local time (0500 GMT/UTC) unless negotiators can agree on another extension, which would be the third of its kind.