Raising a flag for victory against Islamic State in Syria.

The U.S.-backed Syrian Democratic Forces, or SDF, said on Saturday (March 23) that they've captured the militant group's last shred of territory in the east of the country at Baghouz.

The triumph ends I.S.'

Territorial rule over a self-proclaimed caliphate after years of fighting.

However, this might not be the end of the group.

A Reuters journalist said some shooting and mortar fire continued on Saturday morning in Baghouz and an SDF commander warned that the coming phase in the struggle might be even harder.

Some of its fighters still remain in Syria and Iraq, awaiting a chance to rise again and the United States believes the group's leader, Abu Bakr al-Baghdadi, is still alive and living in Iraq.

Further afield, jihadists in Afghanistan, Nigeria and elsewhere have shown no sign of recanting their allegiance to Islamic State.

Intelligence services say its devotees in the West might plot new attacks.

Still, the fall of Baghouz marks a big moment in Syria's eight-year war, wiping out the territory of one of the main factions with the rest split between President Bashar al-Assad, Turkey-backed rebels and the Kurdish-led SDF.

Assad and his Iranian allies have sworn to recapture all of Syria, and Turkey has threatened to drive out the SDF, which it sees as a terrorist group, by force.

The continued presence of U.S. troops in northeast Syria might avert this though.