Lebanon has recently detected, and arrested, ten Sunni Arabs who were affiliated with al Qaeda, and planned attacks on UN peacekeepers along the Israeli border. Another seven members of the terrorist group are being sought. This particular group had Lebanese, Palestinian and Syrian members, and had also planned a series of robberies (of banks and jewelry stores) to finance their terrorist activities.
Two years ago, a wholly Palestinian terrorist gang, Fatah Islam, got into several gun battles with police. Eventually, this fighting went on for weeks, leaving over 400 dead. That was the worst fighting inside Lebanon since the 1975-90 civil war ended.
Fatah Islam was based in a Palestinian refugee camp, Nahr al Bared, in northern Lebanon, outside the port of Tripoli. The refugee camp contains some 36,000 Palestinians. As part of the peace deal that ended the 15 year Lebanese civil war in 1990, the Lebanese security forces cannot enter Palestinian refugee camps. The Palestinians are supposed to police themselves. By and large, they do. But the camps are actually separate towns, surrounded by fences and guarded by Lebanese troops and police. As is happening in the West Bank and Gaza, the Palestinians are feuding among themselves.
Because most Arab states believe Israel must be destroyed, and a Palestinian state established, Palestinian refugees are rarely allowed to become citizens of the countries they are in. As permanent refugees, they have a hard time getting jobs, and get by mainly via foreign aid (with the United States being the largest contributor). Islamic radicalism has become popular among unemployed young men. It feels good to blame the West for all your problems, and to own a gun and be a bad ass outlaw.
The refugee camps have become an excellent hideout for criminals, as long as they are Palestinian, and a recruiting ground for Islamic terrorist groups. One of these was Fatah Islam, which is primarily interested in destroying Israel, and anyone who opposes them. Fatah Islam split from a mainstream Fatah radical group three years ago, and was led by a radical who had been bouncing around the Middle East for years, and was forced to flee Iraq. Fatah Islam was also affiliated with al Qaeda, and sees all non-Moslems as enemies, not to mention "heretical" Moslems like Shias and Druze (which, together, comprise over 40 percent of the Lebanese population.) Nearly 40 percent of Lebanese are Christian, and Sunni Arabs are a minority.
While al Qaeda groups attack Shia Moslems in many other parts of the world, they show restraint in Lebanon because so many Lebanese are Shia. Hezbollah is a major Shia group, and Syria (a Sunni country run by its Shia minority and backed by Shia powerhouse Iran) looks after Shia interests in Lebanon. This new group appears to have been all Sunni, and was willing to go into a Shia dominated area (southern Lebanon) to attack foreign (UN) troops. Apparently, most Lebanese are not eager to see this sort of thing happen, and police were tipped off.