Lebanon's state prosecutor has filed charges against the fugitive leader of Fatah al-Islam in connection with a twin bus bombing near Beirut in 2007.
The attack was seen as an attempt to disrupt Hariri commemorations
Shaker al-Abssi and four Syrian members of his group are accused of planning and carrying out the attack in Ain Alaq in which three people died.
Later in 2007, Lebanese troops battled Fatah al-Islam in a Palestinian refugee camp in north Lebanon.
Hundreds died during months of fighting but Mr Abssi is believed to have fled.
The attack on 13 February 2007 was seen by anti-Syrian politicians as an attempt to disrupt commemorations of the second anniversary of the killing of former Prime Minister Rafik Hariri.
Prosecutor Said Mirza said Palestinian-born Mr Abssi was being charged with incitement to murder over the attack.
His co-accused have been named as Mustafa Siou, alleged to have planted one of the bombs, Kamal Nassan and Yasser Shukeiri.
A fourth man, Omar Hajji, is said to have been killed in the battle at Nahr al-Bared camp.
Mr Siou is reported to have confessed to the plot, as well as to plans to bomb a Shia targets linked to the pro-Syrian opposition group Hezbollah, and Christian ones near offices of the Phalange party, to stir up sectarian strife.