JERUSALEM — The military wing of Hamas, the Islamic group that governs Gaza, announced late Wednesday that it was committed to an Egyptian-brokered cease-fire to end three days of fighting with Israel.

The Hamas wing, the Ezzedine al-Qassam Brigades, said on its Web site that it and the other militant groups in Gaza were responding to “Egyptian efforts to try and stop the aggression against our people.”  

Hamas had joined in the latest round of fighting after a break of more than a year during which the group largely adhered to an informal cease-fire, and the new violence had raised fears of a broader conflict with Israel. But the confrontation remained relatively contained, with the Gaza groups firing mostly short-range rockets that did not reach southern Israel’s major cities.

The Qassam Brigades said that it had kept the “confrontation in this round with the Zionist enemy at the minimal level of fire,” and that it was meant as “a message” to the Israeli leaders.

There was no immediate comment from Israel, but in past rounds, Israeli officials have said that they would judge the militant groups by their deeds and that Israel would respond to quiet with quiet.

Over the past three days, Israel has carried out at least 15 airstrikes against militant squads and sites in Gaza, 11 of them on Tuesday night and Wednesday.

Medical officials in Gaza said Momen al-Adan, 14, was killed Wednesday and his father was seriously hurt in what residents described as an Israeli airstrike in southern Gaza City. The Israeli military had no comment. At least seven other Palestinians were killed in the three days of fighting, most of them said to be militants.

The Palestinian groups — chief among them the Qassam Brigades — have barraged southern Israel with more than 100 rockets and mortar shells since fighting broke out on Monday. One rocket damaged a house in an Israeli village near the border on Wednesday but caused no casualties.

Earlier Wednesday, the Israeli military killed a Palestinian man it said was involved in an attack from the Egyptian Sinai that killed an Israeli construction worker. Another man who the military said played a central role in that attack, which occurred Monday, was severely wounded, the military said in a statement.

Lt. Gen. Benny Gantz, chief of staff of the Israeli Army, said the action taken by his soldiers had prevented a larger attack along the border with Egypt. Speaking at an officers’ graduation ceremony, General Gantz referred to the rocket fire from Gaza and said the Israeli military was “strong and powerful” and “prepared to respond to any threat at any time.”

The military said the two men who were the targets of the strike on Wednesday were terrorists who subscribed to a jihadist ideology that puts fighting for Islam ahead of Palestinian nationalist goals. It said that the wounded man, Mohammed Rashwan, a resident of Rafah in southern Gaza, was a member of the Tawhid and Jihad organization and had been involved in transferring weapons, firing rockets at Israel and smuggling terrorists in and out of Gaza.

The man who was killed, Ghaleb Armilat, had assisted Mr. Rashwan in planning Monday’s attack, according to the military.

Tawhid and Jihad is a shadowy radical Islamic group in Gaza that is believed to be inspired by the ideology of Al Qaeda. The group surfaced in Gaza in 2007, when it claimed to have kidnapped and killed Alan Johnston, a BBC correspondent. Mr. Johnston was later released alive.

In April 2011, the group said it had kidnapped an Italian and threatened to execute him unless Hamas released the group’s imprisoned leader by a set deadline.

The Hamas police stormed a house where they thought the Italian, Vittorio Arrigoni, a pro-Palestinian activist, was being held. After a clash with his abductors, they found his body. The police said he had been hanged.

On Tuesday, a previously unknown jihadist group calling itself the Shura Council of the Mujahedeen in the Environs of Beit al-Maqdes (Beit al-Maqdes refers to Jerusalem) released a video claiming responsibility for Monday’s attack.

The Israeli military said two of the attackers were killed in a clash with Israeli forces when Israeli gunfire detonated explosives on one of their bodies. The video presented two men who it said were on a suicide mission. It said one was a Saudi and the other an Egyptian.

Israeli security officials have expressed increasing alarm about what they describe as the operations of radical Islamic groups in the Sinai Peninsula and their possible links with Gaza.