For three years Raqqa was the de facto capital of Daesh's self-declared caliphate, a centre of operations where it oversaw the management of vast swathes of eastern, central and northern Syria and planned attacks overseas.
The SDF, an alliance of Kurdish and Arab militias, is now fighting Islamic State in the area around Raqqa stadium, said the spokesman Mostafa Bali in a message.
Mahmoud said he could assert that 99 percent of Raqqa was clear of IS fighters, adding that the SDF had to complete the operation of deactivating mines and getting rid of the remnants of the organisation at the hospital.
The fall of Raqqa, where the Islamic State staged euphoric parades after its string of lightning victories in 2014, is a potent symbol of the jihadi movement's collapsing fortunes.
After IS captured Raqa in 2014, the city become synonymous with the militant group's worst abuses and was transformed into a planning center for attacks overseas.
On Tuesday morning, the SDF cleared the last two major IS positions in Raqqa - the municipal stadium and the National Hospital.
In Raqa, only about 300 IS fighters, mostly foreigners, were believed to remain in the last neighborhoods still out of the control of the SDF, a Kurdish-Arab alliance supported by the US-led coalition battling IS in Syria and Iraq.
"The military operations in Raqqa have finished, but there are clearing operations now under way to uncover any sleeper cells there might be and remove mines".
The SDF, backed by a US-led worldwide alliance, has been fighting since June to take the city Islamic State used to plan attacks overseas.
Its capture leaves the group with little more than a "dwarf territory" in neighbouring Deir Ezzor province, said Nicholas Heras, a fellow at the Centre for a New American Security think tank. In Syria, it has been forced back into a strip of the Euphrates Valley and surrounding desert.
But yesterday they captured the hospital and stadium in quick succession, effectively ending IS's more than three-year presence in the city.
The jihadists also suffered setbacks today in the eastern Syrian region of Deir Ezzor, where Russian-backed regime forces retook swathes of territory, further reducing a "caliphate" that three years ago was roughly the size of Britain.
"These are not desert areas, they are villages along the Euphrates (river) that were IS strongholds", the Britain-based monitoring group said".
On Tuesday, a military media unit run by Lebanon's Hizbollah said the Syrian army, which Hizbollah fights with, had pushed into the last Daesh districts of Deir Ezzor city.