For the second time in the last year, Israel has publicized special precautions to deal with Hezbollah terrorist teams seeking revenge for one of their leaders killed two years ago. This time, there was only a vague mention that more security personnel will be assigned to Israeli government officials travelling overseas. Last time, it was additional security personnel assigned to four Israeli legislators (members of the Knesset, or parliament) travelling outside the country. A recent roadside bomb attack directed against Israeli diplomats in Jordan, was believed to be the work of Hezbollah. The attack failed, and the Jordanians are not happy that Hezbollah has been trying that stuff outside of Lebanon. Hezbollah has also been caught trying to kill Jews in Turkey, and the Turks are equally displeased. Hezbollah is gaining lots of new enemies with the vengeance campaign, and Israel is OK with that, as long as no Israelis are killed or kidnapped.
Eighteen months ago, Israel began issuing specific warning to its citizens, to be careful when travelling abroad. The warnings were prompted by Israeli intelligence discovering a Hezbollah effort to kill or kidnap Israeli citizens abroad. This murderous plan was apparently to avenge the February, 2008 assassination of Imad Mughniyeh (a senior Hezbollah leader responsible for attacks that have killed hundreds of Israelis and Americans).
Shortly after Mughniyeh was killed in Syria, Hezbollah began threatening to make attacks against Israeli targets outside of Israel. This has not been done much in the past because Hezbollah relies on fund raising and recruiting among Moslems (especially Shia) living outside the Middle East (especially in the West). But in the past few years, Western counter-terrorism efforts have cracked down on both of these activities. So there is real fear that the furor over Mughniyeh's death will encourage Hezbollah to branch out into international terrorism. The downside of this is increased international efforts against Hezbollah. Logic, however, does not always play with Hezbollah and the Islamic radicals in the Iranian government who provide money and weapons for them.
At first, it was believed that Hezbollah had thought better of going international. Months later, Israeli intelligence began to detect signs that the Mughniyeh revenge operation was on again. Since then, Israeli counter-terrorism efforts have disrupted several Hezbollah murder/kidnap operations overseas. Several other plots are being investigated. Hezbollah has apparently also activated sleeper cells, or sent operatives, to Turkey, Europe, West Africa, Uzbekistan, Thailand and Egypt's Sinai Desert (a popular vacation spot for Israelis.)
Israel cooperates with local counter-terrorism officials, but will go it alone if they believe they can get at a Hezbollah terrorist cell. The Israelis believe that the Hezbollah groups have been ordered to at least murder some Israelis, and to kidnap and get one or more of them back to Lebanon if possible. Kidnapping is very difficult, and it is believed that Hezbollah does not really expect any of its operatives to pull off something like this. Even murder is difficult, especially now that Israeli travelers, and Israeli counter-terror forces are on the alert for this sort of thing.