A new rogue element has emerged in the Israeli-Palestinian gallery: Unknown assailants, widely assumed to be Jewish extremists, have vandalized Muslim cemeteries, mosques and farmlands in a spate of attacks that have put the country on edge.
These attacks, which in recent days have spread from the West Bank into Israel proper, have stoked fears of heightened violence and sparked increasingly agitated calls to find and punish the assailants. On Sunday, Israeli leaders chimed in with condemnations, and police said they were stepping up efforts to halt the violence.
"It's against everything that the Jewish people stand for, as a country and as a democracy," said President Shimon Peres, a Nobel peace laureate. "I am sure that our police will apprehend all the people who did this, the criminals, and we shall not let them walk free."
In the latest incident, vandals sprayed-painted "Death to the Arabs" in Muslim and Christian cemeteries in the Jaffa section of Tel Aviv. The rampage, discovered late Saturday after Yom Kippur, the holiest day in the Jewish calendar, followed a mosque burning last week in an Arab village in northern Israel. The torching set off violent clashes between residents and police in a town that has historically been a model of coexistence.
The two incidents were among the first to take place inside Israel, where Arab residents, in contrast with their Palestinian brethren in the neighboring West Bank, are citizens.
For several years, Israeli settlers have frequently attacked Palestinian targets in the West Bank, vandalizing mosques and uprooting olive trees.
These attacks are meant to protest Israeli government policies seen as sympathetic to the Palestinians, who hope to make the West Bank part of an independent state. Nationalist settlers oppose a Palestinian state on what they say is land promised to the Jews in the Bible.
On Sunday, some 100 settlers attacked a group of Palestinian villagers in their olive groves near Nablus in the northern West Bank with sticks and stones, witnesses said. The army said it rushed to the scene and broke up the clash, allowing the farmers to harvest their crop.
At times, the Israeli army itself has become a target of the settlers, with vandals stoning or slashing the tires of military vehicles. Last week, a crowd of settlers erected a makeshift roadblock to stop a military patrol and clashed with soldiers who got out of a vehicle to clear the road.
The latest bouts of violence appear to be connected to Israel's decision last month to demolish several illegally built structures in the unauthorized West Bank settler outpost of Migron. Settlers are also furious over the death of an Israeli settler and his infant son in a car accident caused by Palestinian stone throwers.
But the spike in West Bank violence has been growing for some time. According to United Nations figures, the number of incidents of settler violence resulting in Palestinian injuries or property damage has risen to 333 this year, compared with 217 in the same period last year.
Israeli human rights groups say the settler violence is the result of years of Israel's unwillingness or inability to take action. The Yesh Din advocacy group, for instance, found that in 642 police complaints filed by West Bank Palestinians between 2005-2010, less than 10 percent resulted in indictments.
Sarit Michaeli of B'Tselem, another rights group, accused Israel of fomenting a "sense of impunity" among settlers.
That may be changing now that the violence is spreading to Israel proper.
It took a matter of hours for Israeli police to make an arrest in last Monday's mosque burning. The suspect, who denied involvement, was identified as an 18-year-old man who until recently, studied at a Jewish seminary in an ultranationalist West Bank settlement. Another suspect was arrested Sunday, Israel Radio reported.
Officials from the police, army and Shin Bet internal security service all said they take the violence extremely seriously. Police said they have stepped up patrols around Arab villages in Israel and are in contact with local Arab leaders to calm tensions.
Settler leaders condemn the violence and say it is the work of a fringe minority.
On Sunday, Prime Minister Benjamin Netanyahu said Israel would not tolerate vandalism against any religious site. "I have instructed the security forces to bring those responsible to justice. We will act against to the fullest extent of the law," he told his Cabinet.
Israeli historian Gershom Gorenberg, whose book "The Unmaking of Israel" deals extensively with settler extremism, said the shift to Israel could mark a change in tactics.
"They are carrying out symbolic actions intended to cause wider conflict between the Palestinian and Jewish populations," he said. "They know this is an escalation, and their goal is to incite that conflict."
Matti Friedman, Daniel Estrin and Daniella Cheslow contributed to this report from Jerusalem.