A Palestinian gunman killed seven people outside an east Jerusalem synagogue during the Jewish Sabbath on Friday, in one of the deadliest attacks targeting Israelis in years that risked sparking widespread violence.

The shooting came a day after a major escalation in the Israeli-Palestinian conflict, including an army raid in the occupied West Bank that killed nine people, rocket fire from Gaza and retaliatory Israeli strikes.

Israel's police chief Kobi Shabtai called the shooting in the Neve Yaakov area "one of the worst attacks we have encountered in recent years." It also fell on International Holocaust Remembrance Day.

Police said that "at around 8:15 pm (1815 GMT) a terrorist arrived at a synagogue in the Neve Yaakov boulevard in Jerusalem and proceeded to shoot at a number of people in the area."

"As a result of the terror attack, seven civilians were pronounced dead and three additional civilians were injured," police said.

They said the gunman fled the scene in a car but was quickly tracked down and killed in an "exchange of fire" with police.

Police have identified the gunman as a Palestinian resident of east Jerusalem, which was annexed by Israel following the 1967 Six-Day War.

The surging violence comes a month after a new government, led by veteran Prime Minister Benjamin Netanyahu, took power.

Netanyahu and his extreme-right National Security Minister Itamar Ben-Gvir visited the scene on Friday, as crowds chanted "death to Arabs," AFP journalists at the scene said.

Speaking on television after visiting the scene, Netanyahu said his security cabinet would soon announce "immediate measures" in response and urged Israelis not to "take the law into their own hands."

- 'Horrific' -

Shalom Borohov, a barber who lives near the synagogue, told AFP that after hearing gunshots he "went down to help people".

"I saw the terrorist arriving with his car. He stopped in the middle of the junction, and shot from his car," continuing to shoot as people came to the scene, he said.

Matanel Almalem, an 18-year-old student who lives nearby, told AFP that he ran down to the street after hearing the shooting and saw the gunman in a white Toyota Corolla.

"I heard a lot of shooting," he said.

US President Joe Biden spoke with Netanyahu to condemn what he called a "horrific terror attack".

"The president made clear that this was an attack against the civilised world," the White House said in a readout of the call, adding that Biden also "stressed the ironclad US commitment to Israel's security".

Just hours earlier, Washington had urged "de-escalation" over the West Bank violence and Gaza rocket fire.

United Nations Secretary-General Antonio Guterres condemned the synagogue shooting as "abhorrent," while France called it "appalling."

Israeli Defence Minister Yoav Gallant, who was on a family visit to the US, has cut short his trip and is returning to Israel, his office told AFP.

"The attack against civilians this Friday evening was horrific," Gallant said in a statement, vowing to "operate decisively and forcefully against terror" and "reach anyone involved in the attack".

In Gaza and several locations across the West Bank, Palestinians celebrated the attack, including in Ramallah, where large crowds cheered and waved Palestinian flags.

- Jenin raid -

Nine people had been killed Thursday in what Israel described as a "counter-terrorism" operation in the Jenin refugee camp.

It was one of the deadliest Israeli army raids in the occupied West Bank since the second intifada, or Palestinian uprising, of 2000 to 2005.

Israel said Islamic Jihad operatives were the target.

Islamic Jihad and Hamas both vowed to retaliate, later firing several rockets at Israeli territory.

Most of the rockets were intercepted by Israeli air defences. The military responded with strikes on Hamas targets in Gaza.

There were no injuries reported on either side, but Gaza's armed groups vowed further action.

After the synagogue shooting, Hamas spokesman Hazem Qassem said the attack proved "the resistance knows how to find the appropriate response" to Israeli "crimes".

Washington had announced Thursday that US Secretary of State Antony Blinken would travel next week to Israel and the Palestinian territories, where he would push for an "end to the cycle of violence".

A State Department spokesman confirmed on Friday that the visit would go ahead and said Blinken would discuss "steps to be taken to de-escalate tensions".

At least 26 Israelis and 200 Palestinians were killed across Israel and the Palestinian territories in 2022, the majority in the West Bank, according to an AFP tally from official sources.