A senior United Nations envoy on Sunday condemned a wave of attacks by Israeli settlers on Palestinian olive groves and called on Israel to punish the perpetrators.
"I am alarmed at recent reports that Israeli settlers in the West Bank have repeatedly attacked Palestinian farmers and destroyed hundreds of their olive trees at the height of the harvest season," Robert Serry, UN special coordinator for the Middle East peace process, said in a statement.
"These acts are reprehensible and I call on the government of Israel to bring those responsible to justice," he added.
Israeli rights group Yesh Din said in a study published on Sunday that it had logged 35 attacks targeting olive trees, grapevines and other fruit trees between September 2011 and July 2012, but that in 99 percent of cases police had closed the investigation files for lack of evidence.
"The phenomenon of tree vandalism continues even more forcefully this year and targets the property and livelihood of many Palestinian families," Yesh Din said.
"The police's failure to enforce the law and protect the Palestinians' property encourages this phenomenon because the criminals who go unpunished are not deterred from repeating their actions." Israeli police spokesman Micky Rosenfeld challenged Yesh Din's findings.
"They are inaccurate and out of date," he told AFP. "Police have stepped up activity, particularly over the past few weeks, in dealing with the incidents which have been taking place."
"There was an undercover police operation which took place just under two weeks ago where three police officers dressed up as Palestinian shepherds were attacked (by settlers)," he said, adding that the officers were specifically watching out for attacks on Palestinian farmers at the time.
"Israeli police have arrested four people who were directly connected in that attack." The threat faced by Palestinian olive farmers during the harvest, which began last week, was raised by senior Palestinian official Hanan Ashrawi in a letter to diplomats.
"Palestinians across the country have begun the annual olive harvest this month and once again they are being attacked by violent Israeli settlers," she wrote in the letter, a copy of which was seen by AFP.
"The Palestinian people request that your mission to our country send observers to all major at-risk olive picking areas to document Israeli settler and military abuses. In addition we believe your presence will be a deterrent to further violence."