The intense internal fighting raging in Syria for the past two years is showing more signs of spreading to neighboring countries. In late February, Syrian army forces fired shells into neighboring Lebanon for the fist time since the conflict broke out in March 2011. Lebanese officials said the attack left four of their citizens dead. Lebanese Sunni Muslims tend to back the rebel forces fighting to topple the regime headed by Syrian dictator Bashar Assad, while Shiite Muslims mostly back Assad, who is a member of the Alowite sect closely related to Shiite Islam. Lebanese President Michal Sleiman, who is a Maronite Catholic, has demanded that Syria halt the shelling forthwith. Clashes have taken place in various parts of Lebanon between supporters and opponents of Assad, whose military forces occupied the country from 1976 until 2005. Syrian troops where withdrawn in the wake of the assassination of Lebanese President Rafic Hariri by Hizbullah agents. Many Lebanese officials believe Assad was behind the killing. Fears are growing that the war in Syria could soon engulf Lebanon as well.