Notices that have been put up in Jerusalem's Merkaz HaRav yeshiva warn students of the presence of a Shabak (General Security Service) agent. The agent is pretending to be a friend of one of the victims of the massacre two weeks ago and is trying to get information from the students, the notices said.

"Keep your eyes and ears open and avoid unnecessary conversations," they added.

The notices explained that a parent of one of the students spoke to the man and understood that he was trying to encourage the boys to give him information that could interest the security forces.