'Operation Roundup'

On September 10, 2018, the US-backed Syrian Democratic Forces (SDF) launch the third phase of "Operation Roundup", to clear eastern Syria of its last IS holdouts.

Under phase one of the operation launched on May 1, the Kurdish-dominated force drives IS from the area around Baghouz in two weeks.

Under phase two, on June 17 it pushes the jihadists from their bastion of Dashisha in Hasakeh province. The village had been one of the last IS-controlled areas in a corridor linking Syria with Iraq.

After initial progress, in late October the SDF is forced to retreat after deadly IS counterattacks. They then announce a temporary halt to the offensive due to bombardments by the Turkish army against Kurdish military positions in northern Syria.

On November 11 the SDF relaunches its operation to seize the last remnants of IS territory, which once covered vast swathes of Syria and Iraq.

Last IS town taken

On December 14, the SDF takes Hajin near the Iraqi border, the last town of note still under IS control.

On January 23, 2019, the Britain-based Syrian Observatory for Human Rights monitor says the SDF has overrun Baghouz, the last IS-held village in Syria.

A day later the jihadists carry out a failed counterattack in a bid to retake the village, of which they still hold a small patch, according to an SDF commander.

On February 7 the international coalition says IS now controls less than one percent of its self-declared caliphate, confirming comments a day earlier by US President Donald Trump.

'Decisive battle' begins

On February 9 the SDF says it has begun the "decisive battle" against the remaining pocket of the jihadists.

"The SDF are advancing slowly in what remains of the IS pocket," Syrian Observatory for Human Rights chief Rami Abdel Rahman says two days later.

Landmines, IS snipers, and tunnels the extremists have dug out for their defence are hindering the advance, he says.

'Human shields'

On February 16 an SDF spokesman says his forces have slowed down their advance to protect the "large numbers" of civilians inside.

SDF commander Jia Furat says civilians are "trapped there as human shields".

On February 22 Human Rights Watch urges the SDF and the US-led coalition to make protecting civilians a priority.

"Witnesses described harrowing conditions in the last months," it says.

They arrive "extremely hungry and dehydrated" and many of them require urgent medical care, the International Rescue Committee says, pointing to new deaths among children.

On February 27 men, women and children packed on trucks leave the last IS patch under the supervision of the SDF, in the fifth evacuation in a week.

A day later the SDF says it has discovered a mass grave containing the severed heads of women near Baghouz.

Final assault

On March 1 the SDF launches its final assault against the last IS redoubt, a riverside encampment in the village of Baghouz.

A day later the SDF says it has breached the jihadists' perimeter. Artillery fire and airstrikes target jihadist positions.

On March 3, the Kurdish-Arab forces slow down its campaign on the last IS pocket to allow tens of thousands of civilians and surrendering jihadists out from their enclave.

The alliance on March 10 says a deadline for surrender has passed and the assault has been resumed.

Cornered on Euphrates banks

On March 19 advancing Kurdish-led forces push diehard IS fighters out of their main encampment, cornering them along the banks of the Euphrates.

The military campaign resumes on March 22 after a pause of two days.

On Saturday, the Kurdish-led forces pronounced the death of the Islamic State's caliphate.

"Syrian Democratic Forces declare total elimination of so-called caliphate and 100 percent territorial defeat of ISIS," spokesman Mustefa Bali said in a statement.