Syrian rebel forces led by Hayat Tahrir al-Sham, or HTS, declared they had ousted President Bashar al-Assad and he had fled Damascus on Sunday. But what is HTS, and how did it rock the long-simmering tensions in Syria? HTS is a Sunni Islamist militant and political group that traces its roots to the beginning of the Syrian civil war.

Syria's main rebel group, Hayat Tahrir al-Sham (HTS), said they are working on taking complete control of the Syrian capital Damascus and promised a new government would take over immediately after its formation.

Rebels in Syria, led by the Islamist alliance Hayat Tahrir al-Sham, or HTS, have captured Damascus, about a week after taking over Aleppo and Hama, and ousted President Bashar al-Assad. As this dramatic shift in the ongoing conflict continues to unfold,

Syria is heading towards stability and Western fears of future chaos and violence are unfounded, the leader of the rebel group who ousted Bashar Al-Assad’s regime has claimed. While Western governments have celebrated the swift toppling of the Assad regime after decades of harsh rule,

Standing before a cheering crowd in Damascus’ historic Umayyad Mosque, the broad and bearded Abu Mohammad al-Jolani declared a new chapter in Syria’s history.

Jolani, a key figure in the Syrian rebellion, has played a crucial role in planning the recent offensive, leading to significant rebel gains, including the capture of Aleppo and Idlib, as the leader of Hayat Tahrir al-Sham (HTS).

Jolani, the rebel leader who led the Hayat Tahrir al-Shams (HTS) group that took over Syria and collapsed President Bashar al-Assad's regime. CBS News' Courtney Kealy breaks down what's known about Jolani.