Human rights groups and U.N. agencies say Israeli settlers in the West Bank have sharply stepped up attacks on Palestinians in a climate of impunity created by lacking law enforcement.

The groups said Wednesday that the number of attacks causing injury or damage rose from 168 in 2009 to 411 in 2011. They say 154 attacks occurred in the first half of 2012.

Jessica Montell of the Israeli group B'Tselem says the violence is not random, but aims in part to remove Palestinians from certain territory. She says the Israeli government has not shown the political will to protect Palestinian civilians, and failed to commit sufficient resources to the job.

Israeli government spokesman Mark Regev denies the claim, saying Israeli police are going after vigilantes.