This file frame grab from video posted online March 18, 2019, by the Aamaq News Agency, a media arm of the Islamic State group, shows an IS fighter firing his weapon during clashes with the Syrian Democratic Forces (SDF) fighters, in Baghouz, Syria. (PHOTO / AAMAQ NEWS AGENCY VIA AP)

DAMASCUS - As the fifth anniversary of the end of the Islamic State's (IS's) geographical control over residential areas in Syria is observed, the group continues attacks in the Syrian desert, a war monitor reported on Sunday.

Despite significant losses in territory, IS continues to pose a threat through a series of deadly attacks, said the Syrian Observatory for Human Rights in a report on the fifth anniversary of the IS defeat.

Since the renowned battle of Baghouz in the Deir al-Zour province in eastern Syria, which marked the end of IS territorial dominance, the group has resorted to guerrilla tactics, launching hit-and-run operations, ambushes, roadside bombings and direct assaults on military installations, it said.

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While IS may have lost its grip on populated areas, it continues to operate as a clandestine force, exploiting the vast expanse of the Syrian desert to regroup and launch attacks, it said, adding that these attacks have targeted both Syrian military forces and civilian populations, resulting in a continued loss of life and instability in the region.