JERUSALEM — The Israeli military said it downed a drone launched by Gaza militants on Monday, the first time it encountered an unmanned aircraft since the start of its offensive last week, as new Israeli airstrikes pushed the death toll from Israeli airstrikes to at least 175.

Israel began its campaign against militants in the Hamas-controlled Gaza last Tuesday, saying it was responding to heavy rocket fire from the densely populated territory. The military says it has launched more than 1,300 airstrikes since then, while Palestinian militants have launched nearly 1,000 rockets at Israel.

The outbreak of violence followed the kidnappings and killings of three Israeli teenagers in the West Bank last month, as well as the subsequent kidnapping and killing of a Palestinian teenager in an apparent revenge attack, along with Israeli raids against Hamas militants and infrastructure in the West Bank.

Three Jews were charged Monday in the killing of the Palestinian teen, whose death set off days of violent protests in Arab areas of Jerusalem and northern Israel.

Police spokesman Micky Rosenfeld says the three appeared before a court on Monday. He said the suspects admitted to abducting 16-year-old Mohammed Abu Khdeir and setting him on fire. Rosenfeld said they also re-enacted the murder.

Abu Khdeir was taken on July 2 near his home in east Jerusalem and his charred body was later found in a forest. An autopsy found that he was burned to death.

Israel’s Shin Bet security service said the suspects, whose names were not released, were motivated by revenge after the kidnapping and killing of three Israeli teenagers.

Police are investigating three other suspects who remain under house arrest for involvement in the killing.

Meanwhile, two Israeli airstrikes struck the southern Gaza city of Khan Younis, killing four Palestinians, according to officials from the city’s European Hospital.

The officials said Saddam Moamar, his wife Hanadai, and his father Mousa were killed by an airstrike that hit their house. Their neighbor, Maher Abu Mor, was killed in another airstrike while standing on the rooftop of his home, the officials said, speaking on condition of anonymity because they were not authorized to talk to media.

It was not immediately clear why their homes were targeted.

In all, the Palestinian Health Ministry in Gaza has said that at least 175 people have been killed in Israeli air attacks, including dozens of civilians.

No Israelis have been killed as a result of Hamas rocket launches, in large part thanks to the success of Israeli military’s ‘Iron Dome’ air defense system in intercepting the missiles. Several people have been wounded, however, including a teenage boy who was seriously injured by rocket shrapnel on Sunday.

The Israeli military said the drone, launched from Gaza on Monday, was shot down in mid-flight by a Patriot surface-to-air missile along the southern Israeli coastline, near the city of Ashdod. In a statement to media, Hamas claimed it launched three drones at Israel on Monday, though the military insisted there was only one.

Hamas said it has developed two types of drones — one for intelligence gathering, and one for delivering munitions. It also said it lost contact with one of the drones and that the targets included the Israeli Defense Ministry compound in Tel Aviv.

It was the first time the militant group publicly acknowledged it has drones in its arsenal.

The use of drones with an offensive capacity could inflict significant casualties — something the rockets from Gaza have failed to do, largely because of the success of the Israeli military’s ‘Iron Dome’ air defense system in shooting them down.

“Hamas is trying everything it can to produce some kind of achievement and it is crucial that we maintain our high state of readiness,” Israeli Defense Minister Moshe Yaalon said. “The shooting down of a drone this morning by our air defense system is an example of their efforts to strike at us in any way possible.”

Israeli Prime Minister Benjamin Netanyahu said Sunday that the current Israeli operation could last for “a long time” and that the military was prepared “for all possibilities.” That includes a Gaza ground operation, which would likely cause heavy casualties in the coastal strip.

But Netanyahu is coming under increasing international pressure to end the operation soon. On Sunday, U.N. Secretary-General Ban Ki-moon called for an immediate cease-fire while U.S. Secretary of State John Kerry voiced American “readiness” to help restore calm. Egypt, a key mediator between Israel and Hamas, continued to work behind the scenes to stop the conflict.

Hamas has sent signals it may be ready to consider a cease-fire and has demanded that hundreds of recently arrested activists be freed as part of any prospective truce.

For his part, Netanyahu is likely seeking to show the Israeli public that he has succeeded in significantly degrading Hamas’s ability to strike at Israeli targets before moving ahead diplomatically.

Also Monday, a 21-year-old Palestinian was killed during confrontations with Israeli soldiers in the West Bank village of Samoa, near Hebron, Palestinian health officials said. Residents of the village said soldiers opened fire at a group of Palestinians who were throwing stones at them. The officials and the villagers spoke on condition of anonymity because they were not authorized to talk to media.

The Israeli army confirmed the death and said it was looking into the incident.