A hard-line Palestinian military commander who rebelled against leader Yasser Arafat to form his own rival party died in Damascus on Tuesday, according to his representatives and hospital officials. Said Musa Maragha, better known by his nom de guerre, "Abu Musa," was 86.

They said Maragha died of cancer.

Maragha, a Jordanian of Palestinian descent, defected from the Jordanian army in 1970 over tensions between the military and Palestinian fighters who were using the kingdom as a base to carry out attacks against Israel.

Palestinian fighters were pushed out of Jordan in 1971 in battles with Jordanian forces that killed thousands, mostly Palestinians, later known as "Black September."

Many fighters, including Maragha, fled to Lebanon.

There he joined the Fatah movement, headed by charismatic leader Arafat. Fatah at the time was aiming to destroy Israel and create a Palestinian state in its place, demanding the return of hundreds of thousands Palestinian refugees who fled or were forced from their homes during the 1948 Mideast war surrounding the creation of the Jewish state.

Decades later, the movement changed its goal to establishing a Palestinian state alongside Israel in territories seized in the 1967 Mideast war — the West Bank, Gaza Strip and east Jerusalem, while still demanding the return of the refugees to Israel.

Maragha quickly rose through the ranks of ragtag Palestinian fighting forces. By 1976, he was Fatah's chief military operative in south Lebanon, where Palestinians had carved out an enclave to attack neighboring Israel.

Maragha also involved Palestinians in Lebanon's 15-year civil war that ended in 1990, battling Syrian forces that intervened to assist Christian militias against their Muslim and leftist rivals.

Maragha rebelled against Arafat in 1982, after Israel invaded southern Lebanon and bombed the capital, Beirut, pushing out Palestinian fighters. Arafat and much of the Palestinian leadership fled to establish a base in Tunisia. Other fighters fled to Algeria and Yemen.

Maragha wanted Arafat to hold military commanders accountable for fleeing from the fighting. He argued against leaving Beirut, wanting to stay as close as possible to Israel's borders.

A year later, he established a rival group, called "Fatah Uprising." The group received the backing of the Assad regime in Syria, which sought to weaken Arafat.

He ultimately left to Damascus, where he joined the Syria-allied Palestinian National Alliance, a group that rejected negotiations with Israel.

The alliance failed to gain significant traction among Palestinians.

Maragha slowly slipped into obscurity following interim peace accords signed between Arafat's Palestine Liberation Organization and Israel, starting in 1993.

He was born in the biblical village of Bethany, near Jerusalem, a Palestinian town known now by its Arabic name, Azariyeh.

It was not immediately clear where or when Maragha would be buried. Representatives said there was heavy fighting between Syrian rebels and government forces around the cemetery in the Palestinian refugee camp of Yarmouk in Damascus.

He is survived by four children.