JERUSALEM — Israeli airstrikes killed nine children and 15 others in Gaza on Monday, Palestinian officials said, after some of the worst clashes in Jerusalem in recent years rapidly escalated into an exchange of rockets and bombs between the militant group Hamas and the Israeli military.

The Israeli airstrikes came after Hamas fired seven rockets at Jerusalem — the first time the city had been targeted since 2014 — and 200 more at southern Israel. Earlier in the day, violent clashes near al-Aqsa Mosque in Jerusalem's Old City between Israeli police and Arab protesters left more than 300 Palestinians injured.

Hamas, which controls the Gaza Strip, warned that it was prepared to escalate further by targeting Tel Aviv in addition to Jerusalem, and by the end of the night it had fired about 200 rockets into Israel, according to the Israeli military. No fatalities were reported. An Israeli in the southern city of Sderot was lightly injured after his car was hit by a Hamas antitank missile.

Israeli military spokesman Hidai Zilberman said Israeli forces were preparing for a range of scenarios, including "increased air defense and ground reinforcements." The military said its airstrikes had killed eight Palestinian militants and destroyed a tunnel they used for attacks on Israel.

Israeli Prime Minister Benjamin Netanyahu warned Monday night: "The terrorist organizations in Gaza crossed a red line and attacked us with missiles at the entrances to Jerusalem. Israel will respond with great force." He added, "We did not want to escalate, but those who chose to escalate will be hit forcefully."

The exchange of fire across the Israel-Gaza border came after running clashes erupted earlier in the day among Israeli police, Palestinian protesters and far-right Israelis around the Old City. Tensions have been rising amid a court effort by a Jewish settler group to evict six Palestinian families from their homes in Sheikh Jarrah, a mostly Palestinian neighborhood in East Jerusalem.

Five Israelis were wounded in the clashes, according to Hadassah Hospital in Jerusalem. Among them was a 7-month-old baby who suffered a head injury after a rock was thrown at her family's car.

Among the hundreds of Palestinians injured were seven who were hospitalized in serious condition, according to the Red Crescent. Video footage circulated on social media of Israeli police officers brutally beating a detained Palestinian man. Over the weekend, more than 250 Palestinians were hurt in similar clashes.

In a statement, a State Department spokesman said the United States condemned the rocket attacks on Israel from Gaza "in the strongest possible terms." He continued, "While we urge de-escalation on all sides, we also recognize Israel's legitimate right to defend itself and to defend its people and its territory."

Much of the recent violence has occurred at and around the holy site known as the Temple Mount by Jews and as the Noble Sanctuary by Muslims. Thousands of Palestinians have sought to pray there during Ramadan, the holy fasting month that ends this week.

"The Israelis don't want us to pray. They want to keep us from our mosque," said Ahmad, a young Palestinian man who refused to give his last name out of security concerns, standing near several Red Crescent ambulances and a line of Israeli police officers in riot gear.

The site is also a focus of Israeli nationalists who on Monday celebrated Jerusalem Day, a national holiday often marked by provocative flag parades through Palestinian neighborhoods in the Old City. Netanyahu announced a last-minute decision Monday to reroute that procession, preventing what could have been even greater violence in the city.

"Why is Jerusalem one of the only cities in the world where Jews cannot go? If you are American, you are allowed to walk around Washington, D.C., aren't you?" asked Roger Zini, 59, a participant in the flag parade.

Zini, among the last Jewish marchers to cross a metal police barrier that temporarily blocked the parade from entering the Old City, dismissed the risk of violence, saying the Jewish marchers wanted only to reach the sacred Western Wall.

“If the police want to prevent violence, they should stop the violent people, not people who just want to walk,” he said.

Rock-throwing Palestinians and Israeli police firing stun grenades clashed outside al-Aqsa Mosque May 10, in ongoing violence in Jerusalem. (Reuters)

In the neighborhood of Sheikh Jarrah, clashes broke out Monday after a visit by far-right, pro-settler politicians. Since last week, solidarity protests by Palestinians have turned into confrontations with the police. The Israeli Supreme Court had been scheduled to hear a petition to evict the Palestinian families, but the hearing was postponed.

In a tour of the neighborhood, Bezalel Smotrich, the head of the pro-settler Religious Zionist party, blamed the recent surge in violence on Israeli politicians who are in negotiations to form a new government and are expected to invite the indirect support of an Arab party to reach a parliamentary majority.

“Every time Israel tries to compromise with the Arabs who deny our right to exist, terror runs wild,” said Smotrich.

Throughout the day, small-scale skirmishes broke out in and near the Old City, with Israeli police hurling stun grenades at Palestinians who were gathering on the street and chanting “Allahu akbar,” “al-Aqsa forever” and other slogans.

“The Israeli occupation forces’ brutal storming and assault on worshipers in the blessed al-Aqsa Mosque and its courtyards is a new challenge to the international community, especially those efforts being made by the United States administration,” said Nabil Abu Rudeineh, a spokesman for Palestinian Authority President Mahmoud Abbas.

Daniel Seidemann, an Israeli lawyer specializing in Jerusalem politics, said that while neither the volatility nor the mass grass-roots resistance movements are new, what has changed in this latest round of violence is that there’s no “responsible adult.” Israel is in the midst of a years-long political stalemate that has deprived the country of a fully functioning government, he noted, while relations with the neighboring Jordanian king, who could have influence on the situation, are at a low point.

In the past, Seidemann said, tamping down the flames of conflict “required a prime minister in Israel, which we don’t have, a king who’s talking to him and a Washington that is willing to do something.”

For the majority of his 12 years in office, Netanyahu maintained a relative status quo on the Temple Mount, but experts say the dynamics have recently changed.

Amid an increasingly dire struggle for political survival, Netanyahu has lent prominence to once-fringe anti-Arab activists who vocally call for Jewish control of the Temple Mount, such as Jewish Power leader Itamar Ben Gvir. With Netanyahu’s support, Ben Gvir joined the Knesset in the last round of elections in March.

In protesting the police decision forbidding Jewish entry to the area, Ben Gvir said he had notified Netanyahu’s Likud party that he would withhold his votes in the Knesset in the coming week.

In a Facebook post, speaking amid a crowd of Jewish worshipers at the entrance to the site, he said that Netanyahu and Israel’s security chiefs had “surrendered to terrorists at the Temple Mount.”

Rubin reported from Tel Aviv. Hazem Balousha in Gaza contributed to this report.