Israel airstrikes hit Gaza after rocket attacks, clashes intensify in Jerusalem.
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.