Diplomats and Middle East experts cautioned that cease-fire agreements are precarious things, even as the deal between Hamas and Israel was reached on Thursday.
As the near-simultaneous announcements were made late Thursday, sirens sounded in Israeli towns bordering the Gaza Strip, indicating that militants were continuing to fire rockets.
After announcing the agreement on Thursday, Prime Minister Benjamin Netanyahu’s office warned that “the reality on the ground will determine the continuation of the campaign.”
Similarly, a Hamas spokesman, Taher al-Nono, said on Thursday, “the Palestinian resistance will abide by this agreement as long as the occupation abides by it.”
No immediate violations were reported after the cease-fire began officially at 2 a.m. local time Friday.
Officially, Israel denied earlier this week that cease-fire negotiations were taking place or that a deal was imminent, but that may have been a tactic designed to put pressure on Hamas.
The senior Israeli representative in the negotiations — which Egypt helped coordinate — has been the national security adviser, Meir Ben-Shabbat, who is considered close to Mr. Netanyahu.
The two senior Hamas figures involved in the negotiations have close ties to Egyptian intelligence.
The Egyptians have sometimes had trouble contacting senior Hamas officials, who have often fled underground and ceased using electronic devices because they fear Israeli attempts to kill them.