US Vice President Joe Biden Wednesday criticized Palestinians for their "failure to condemn" a months-long spree of stabbing attacks by Palestinians against Israelis, but also warned Israel that force alone would not stop the attacks.
Israel has been on edge for more than five months amid random attacks by Palestinians on Israelis, many of them stabbings, which have left scores dead, including, while Biden was visiting, a US citizen.
The newest attacks have left a cloud over Biden's first talks in Israel and the Palestinian areas in six years.
Biden met former Israeli president Shimon Peres in the southern Tel Aviv suburb of Jaffa late Tuesday, just as a Palestinian identified as Bashar Masalhah, 22, went on a stabbing spree nearby, killing US tourist Taylor Force and injuring a dozen others.
In a news conference with Israeli Prime Minister Benjamin Netanyahu in Jerusalem Wednesday, Biden said his wife and grandchildren had been having dinner on the beach just hundreds of metres from the stabbing spree.
Force was a 28-year-old MBA student at Vanderbilt University and a war veteran who served in Iraq and Afghanistan.
In the wake of the attack, the Fatah party of Palestinian President Mahmoud Abbas posted a cartoon on its Twitter account of a hand holding a knife over a map of Israel and the Palestinian territories, calling the stabber from Tuesday's attack a "hero" and "martyr."
Biden condemned Fatah's glorification of the stabber.
"Let me say in no uncertain terms: the United States of America condemns these acts and condemns the failure to condemn these acts. This cannot become an accepted modus operandi. This cannot be viewed by civilized leaders as an appropriate way in which to behave," he told the morning news conference with Netanyahu.
Slamming Abbas and his secular Fatah party, Netanyahu said he appreciated Biden's unequivocal condemnation and demanded other world leaders do the same.
Netanyahu called the US victim a "hero" and expressed his "deep condolences."
But, while meeting Israeli President Reuven Rivlin for lunch, Biden added that, while Israel had the full right to defend itself, ending violence "cannot and will not be done just by physical force."
Rivlin too said that "terror and hatred drive people apart. The only way forward is to build trust. Peace cannot be imposed, it must be reached."
There were four attacks in Jerusalem and in the Tel Aviv area on Tuesday, in which four Palestinian attackers were killed and some 15 Jewish and Arab Israelis injured.
Palestinians attempted two more attacks on Wednesday, the Israeli police and military said.
Two gunmen were shot dead in a gunbattle with authorities in Jerusalem after they opened fire in the city from a car, seriously injuring a civilian, police spokesman Micky Rosenfeld said.
Another Palestinian tried to stab a member of the Israeli security forces guarding a checkpoint near the West Bank city of Qalqiliya, but was shot dead, the Israeli military said.
Jerusalem was on top alert as Biden met Netanyahu and Rivlin in the city, ahead of evening talks with Abbas in the nearby West Bank city of Ramallah.
Netanyahu's security cabinet, in an emergency meeting overnight, approved several stringent measures, including closing gaps in the controversial security wall in East Jerusalem.
Palestinians have launched scores of knife attacks against Israelis since early October, protesting perceived Israeli violations - vehemently denied by Israel - at a disputed Jerusalem holy site, as well as the ongoing occupation.
The last attempt at peace talks collapsed two years ago.
Israel blames the violence on inflammatory rhetoric by radical Muslim leaders, who call on youths to kill Jews to "defend" Jerusalem's al-Aqsa Mosque and glorify attackers as "martyrs" and "heroes."
Palestinians blame the violence on oppression.
More than 180 Palestinians - most of them knife attackers - and 30 Israelis have been killed.