A rocket fired from the Gaza Strip has struck an uninhabited area outside of Jerusalem, causing no damage or injuries, the Israeli army has said, shortly after air raid sirens wailed across the city.
Israeli police spokesman Micky Rosenfeld said the rocket landed on Friday in an open area near Gush Ezion, which includes several Jewish settlements and Arab villages in the occupied West Bank southeast of the city.
The unprecedented attack came as Israel pounded the Gaza Strip for a third day in fighting that has left 29 Palestinians and three Israelis dead.
The armed wing of the Palestinian Hamas movement confirmed it had fired a Qassam rocket towards Jerusalem.
An attack on Israel's self-declared capital marks a major escalation by Gaza fighters, both for its symbolism and its distance from the Palestinian territory.
Located roughly 75km away from the Gaza border, Jerusalem had been thought to be beyond the range of Gaza rocket squads.
Fighters had already launched rockets at Tel Aviv, another first, on Thursday and Friday.
The Israeli government on Friday night gave a green light to recruit up to 75,000 reservists, a possible sign that Israel was preparing for a ground offensive in Gaza.
The decision was taken during a cabinet meeting in Jerusalem. It does not necessarily mean that all 75,000 will be called up, though.
Earlier on Friday, Palestinian demonstrators protested against Israel's military operations in Gaza at the Damascus gate in Old Jerusalem.
Several protesters were detained as clashes with police occurred. Protesters also burned tyres at the Qalandia checkpoint near the city of Ramallah in the occupied West Bank.
Binyamin Netanyahu, Israel's prime minister, called Barack Obama, the US president, on Friday, with the two men discussing options for "de-escalating" the situation, the White House said.
Obama "reiterated US support for Israel's right to defend itself, and expressed regret over the loss of Israeli and
Palestinian civilian lives," according to a US statement on the call.
Three days of fighting between Israel and Gaza fighters continued on Friday with numerous Israeli air strikes hitting the tiny Palestinian territory.
The operation began on Wednesday with the assassination of Hamas' military chief Ahmad Jabari and dozens of air strikes on rocket launching sites.
After days of battering targets with air strikes in Gaza, Israeli forces were massing along the border in preparation for a possible ground invasion.
Al Jazeera's Jacky Rowland, reporting from Gaza, said: "We have seen an intensification of firing from both sides.
"If the Israeli army is seeking to kill those firing rockets, the fighters are not in those locations. We are seeing the fighters have far more sophisticated weapons now, especially in the actual launching systems.
"They are able to operate them via remote control. They have been buried in the ground either days or weeks ago, so trying to target these locations is rather futile."