TEL AVIV, Israel — Israel launched air strikes on the Gaza Strip late Friday in response to rocket attacks by Palestinian militants, as tensions in Jerusalem spilled over into the worst round of cross-border violence in months.
The barrage of rocket fire came as hundreds of Palestinians clashed with Israeli police in east Jerusalem in which at least 4 police and 6 protesters were injured. The clashes have become a nightly occurrence during the Muslim holy month of Ramadan.
Israel's military said 36 rockets were fired from Gaza during the night, shortly after its Islamist rulers issued a call for Palestinian resistance in Jerusalem. Israeli aircraft retaliated with strikes on Hamas rocket launchers and underground infrastructure, the military added.
There were no immediate reports of casualties in Gaza or on the Israeli side of the border.
The pre-dawn exchange of fire broke months of relative quiet on the Israel-Gaza frontier, although it did not appear to signal a wider escalation. The Israeli military said it was not imposing any safety restrictions on Israelis living near the border.
The United Nations said it was working with all parties to calm tensions.
"I am alarmed by the recent escalations in Jerusalem and around Gaza," Tor Wennesland U.N. Special Coordinator for the Middle East Peace Process said in a statement on Saturday.
"I reiterate my call upon all sides to exercise maximum restraint and avoid further escalation, particularly during the holy month of Ramadan and this politically charged time for all."
Inside Jerusalem, the unrest resumed on Friday night as Palestinian youths gathered outside the walled Old City and scuffled with hundreds of Israeli police some on horses and in riot gear, and organized protests by ultra-nationalist Israelis chanting anti-Arab slogans.
Palestinians pelted stones towards police firing water cannons. Others hurled rocks at an Israeli court building and smashed security cameras. The Palestine Red Crescent said eight Palestinians were injured.
Palestinians say police have tried to prevent them from holding their usual Ramadan evening gatherings after prayers outside the Old City's Damascus Gate by erecting metal barriers in its amphitheater-style plaza. The historic landmark on the north side of the Old City is adjacent to several Palestinian neighborhoods.
The Old City is home to a sensitive holy site known to Muslims as the Noble Sanctuary and to Jews as the Temple Mount. The site, home to the Al-Aqsa mosque compound, is the third-holiest site in Islam. It is also among the holiest sites in Judaism, revered as the spot where the biblical Temples once stood.
A spokesperson for Jerusalem District Police said in a statement that officers would "continue to work to maintain order and prevent violent riots, harming the security of the public" and use "the means and capabilities available to it, arresting those involved and prosecuting them."
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But Dr. Mustafa Barghouti Secretary General of the Palestinian National Initiative Movement, a political party, told NBC News that young Palestinians would continue to defend the Arab identity of their city and its future.
"The youth of Jerusalem have proven that they are the protectors of their city in the face of settler fascism and the occupation army," he said.
Elsewhere, in the occupied West Bank, Palestinians clashed with Israeli troops around military checkpoints. Israel's border police said it dispersed hundreds hurling stones and fire-bombs.
Jerusalem is at the core of the Israeli-Palestinian conflict. Israel claims the whole city, including its eastern sector captured in a 1967 war, as its capital. Palestinians seek to make East Jerusalem the capital of a future Palestinian state in the West Bank and Gaza.
Paul Goldman reported from Tel Aviv, Lawahez Jabari from Jerusalem and Adela Suliman from London.
Reuters contributed to this report.