JERUSALEM – Israel dispatched a beefed-up security force to its main airport Thursday and asked foreign airlines to prevent blacklisted travelers from boarding Tel Aviv-bound flights, ahead of the anticipated arrival of hundreds of pro-Palestinian activists.

The activists, who say their mission is peaceful, have placed Israel in an awkward position: authorities seem torn between their determination to keep out people they consider hostile agitators and a sense that they may be taking the bait en route to another public relations debacle.

By Thursday evening, eight people had been blocked from boarding one flight in Paris. No activists had arrived in Israel by 1 a.m. today.