JERUSALEM — Both Israel and the Islamic Jihad militant group in Gaza indicated Tuesday that they would abide by an Egyptian-brokered truce ending four days of cross-border fighting, but each warned that maintaining the calm would depend on the actions of the other side.

Bary Mike cleaned up his store in the port city of Ashdod on Tuesday. A rocket fired from Gaza had landed near his business.

“Our message is clear: quiet will lead to quiet,” Prime Minister Benjamin Netanyahu of Israel told an audience in Jerusalem, adding, “Anyone who violates it, or even tries to violate it, will be in our sights.”

Islamic Jihad, the main group responsible for launching about 170 rockets into southern Israel since Friday, said it had agreed to stop firing after receiving guarantees that Israel would not embark on a new wave of violence by “assassinating” any militant commander in the Gaza Strip, which is led by the Islamic group Hamas.

“We are part of the cease-fire, and our commitment to it depends on the level of commitment” of Israel, an Islamic Jihad leader, Khadir Habeeb, told reporters in Gaza.

Hamas sought the aid of Egyptian mediators to broker unannounced understandings with Israel to end the violence. The truce came into effect before dawn on Tuesday.

Its fragility was apparent from the start.

The last Israeli airstrike against a squad launching rockets occurred Monday night. But several Palestinian rockets and mortar shells landed in Israeli territory throughout Tuesday. Most fell in areas near the Gaza border, but on Tuesday night a longer-range rocket slammed into a parking lot in a residential neighborhood of the southern Israeli town of Netivot. The rockets caused no physical injury, and Israel did not immediately respond.

The latest round began Friday when Israeli air-to-ground missiles killed Zuhair al-Qissi, the leader of the Popular Resistance Committees, a militant group. Israel holds the group responsible for the deadly attack last August from across the border with Egypt in which eight Israelis were killed.

Israel said that by killing the leader and an assistant as they drove in a car, it had acted to thwart a similar attack that was being planned.

Islamic Jihad took the lead in retaliating, firing barrages of rockets at Israel, while Israel carried out more than 30 airstrikes against rocket launching sites and other facilities, killing about 25 Palestinians, most of them militants.