The Shin Bet (Israel Security Agency) has developed over the years a number of different methods for gathering intelligence within Jewish settlements in the West Bank. The Shin Bet's Jewish Department operates throughout the country and not just in the West Bank. It uses electronic intelligence-gathering technology but also plants agents inside organizations and some of the more radical settlements and outposts to help uncover potential terror plots. While the focus of the department appears to be in the West Bank, the Shin Bet also invests significant resources in Israeli cities with mixed Jewish and Arab populations such as Jaffa, Ramle, Beersheba and Acre. The Yasuf arsonists left graffiti reading "Price tag - greetings from Effi." But the likelihood that "Effi" is the name of one of the arsonists is extremely slim, explained Yitzhak Pantik, a former head of the Shin Bet's Jewish Department. Nevertheless, the Shin Bet and police are likely searching through all of the Effis that they have listed on various right-wing watch lists. "If this was done by Jews you think one of them would leave his name," he asked. "This was probably their way of trying to throw security forces off the track." Anti-Palestinian attacks, Pantik said, would likely escalate as settler frustration grows regarding the government-imposed freeze on settlement construction. "Any diplomatic initiative will lead to an escalation in violence and efforts by extremists to torpedo it," he said. But settlers contacted by the The Jerusalem Post on Sunday said they had no knowledge of the attack. Some speculated that the Effi who was mentioned could even be a member of the Shin Bet looking to smear settlers. In a statement it released on Saturday night the Samaria Regional Council noted, "who would be stupid enough to leave a name?" Tovah Lazaroff contributed to this report.