ISIL continued to exploit local instability, sectarian rifts and weak state control to regroup and conduct attacks. As of late 2025, the group’s overall strength was estimated at 3 000 fighters across the Syrian and Iraqi region, most of them based in Syria.217 Using the chaos that ensued the collapse of the Al-Assad regime, ISIL operatives moved into cities across Syria,218 exploiting security vacuums to regroup and mount attacks.219 As of late 2025, the group maintained sleeper cells in various urban zones including Damascus and networks encompassing all governorates.220 The UN Sanctions Monitoring Team indicated that, according to Member States, ISIL had infiltrated government security forces, especially at mid-level and lower ranks, and created a special battalion for complex and high-profile attacks. The group has acquired new weaponry such as anti-tank missiles, anti-aircraft systems and mortars after the fall of the Assad regime.221 Attacks attributed to the group in 2025 involved IEDs, VBIEDs, ambushes and targeted killings. While Deir Ez-Zor remained ISIL’s main theatre of operations,222 such attacks were also reported in Raqqa,223 Idlib,224 Aleppo225 and Palmyra city,226 while the group apparently also re-emerged in the south.227
Since late November 2025, ISIL has expanded its previous focus on the SDF to target government military forces228 with greater frequency.229 On 21 February 2026 ISIL spokesperson Abu Hudhayfa al-Ansari declared a ‘new phase of operations,’230 calling for confronting the transitional government which he referred to as being ‘secular’. Following this statement, the group’s operations spiked temporarily.231 Between mid-February and mid-May 2026, SOHR recorded that ISIL attacks in government-controlled areas killed 31 members of the government forces,232 although the pace of attacks by the group has significantly decreased since late March/early April 2026.233 Meanwhile, there continued to be some instances of the group targeting Shia Muslims.234
According to the UN, in 2025, the transitional government arrested at least 278 suspected ISIL members, foiled 45 planned attacks, and dismantled 23 cells, seizing weapons and explosives.235 Between 8 December 2024 and January 2026, the transitional government reported that it arrested 620 ISIL members, most of whom were held in dilapidated facilities in need of renovation, and pending judicial reforms and related proceedings.236 The transitional government attributed the 2025 attacks on Mar Elias church in Damascus and the Ali Bin Abi Talib Mosque in Homs to ISIL, stating that those responsible have been arrested.237 Arrests of ISIL suspects continued to be reported, the authorities stating that investigations pertaining to detainees are ongoing under legal procedures before any judicial action is taken.238
There were large-scale operations by the US-led Global Coalition against ISIL,239 especially in response to a 13 December 2025 deadly attack on US forces.240 By mid-February 2026, the US Central Command (CENTCOM) stated that its forces had struck over 100 ISIL targets and arrested or killed 50 ISIL fighters since December 2025.241 Counter-terrorism operations were conducted jointly with the SDF and, from August 2025, with some participation of transitional government forces.242
- 217
UN Security Council, Thirty-seventh report of the Analytical Support and Sanctions Monitoring Team submitted pursuant to resolution 2734 (2024) concerning ISIL (Da’esh), Al-Qaida and associated individuals and entities, S/2026/44, 4 February 2026, url, para. 50
- 218
Al Jazeera, Analysis: ISIL attacks could undermine US-Syria security collaboration, 27 December 2025, url
- 219
USDOD, Operation Inherent Resolve And Other U.S. Government activities related to Iraq & Syria, July 1, 2025 – December 31, 2025, 17 February 2026, url, p. 13
- 220
UN Security Council, Thirty-seventh report of the Analytical Support and Sanctions Monitoring Team submitted pursuant to resolution 2734 (2024) concerning ISIL (Da’esh), Al-Qaida and associated individuals and entities, S/2026/44, 4 February 2026, url, para. 54
- 221
UN Security Council, Thirty-seventh report of the Analytical Support and Sanctions Monitoring Team submitted pursuant to resolution 2734 (2024) concerning ISIL (Da’esh), Al-Qaida and associated individuals and entities, S/2026/44, 4 February 2026, url, para. 55-56
- 222
UN Security Council, Thirty-seventh report of the Analytical Support and Sanctions Monitoring Team submitted pursuant to resolution 2734 (2024) concerning ISIL (Da’esh), Al-Qaida and associated individuals and entities, S/2026/44, 4 February 2026, url, para. 54
- 223
Enab Baladi, Islamic State Claims Two Attacks in Syria in Two Days, 18 April 2026, url; Akil, S., Fallout Risks: What the Regional War Means for Syria, TIMEP, 20 March 2026, url; ISW and CTP, ISIS Attacks in Northeastern Syria since February 18, February 24, 2026 at 2:00 PM ET, 24 February 2026, url
- 224
Kurdistan24, ISIS Claims Deadly Attack on Syrian Security Patrol in Idlib Province, 15 December 2025, url
- 225
Enab Baladi, Islamic State claims attack in Aleppo as assaults escalate, 7 March 2026, url; ISW and CTP, Likely ISIS-Affiliated Attack in Aleppo City on December 31, 2025, 2 January 2026, url
- 226
International Crisis Group, Palmyra Attack Exposes Syria’s Security Sector Vulnerabilities, 15 December 2025, url
- 227
Etana Syria, Brief: Rising instability in south-west Syria, 8 October 2025, url
- 228
UN Security Council, Thirty-seventh report of the Analytical Support and Sanctions Monitoring Team submitted pursuant to resolution 2734 (2024) concerning ISIL (Da’esh), Al-Qaida and associated individuals and entities, S/2026/44, 4 February 2026, url, para. 54
- 229
Zelin, A., Where ISIS is still active today, NPR, 19 December 2025, url
- 230
Reuters, Islamic State claims two attacks on Syrian army, announces ‘new phase’ of operations, 21 February 2026, url
- 231
Enab Baladi, Islamic State claims attack in Aleppo as assaults escalate, 7 March 2026, url
- 232
SOHR, ISIS claims responsibility for attack on bus of 64th Division in western Al-Hasakah, 12 May 2026, url
- 233
MEI, The Collapse of ISIS in Syria, 8 June 2026, url; Asharq Al-Awsat, ISIS Shifts Priorities, Seeks to Raise Cost of Rule in Syria, 22 April 2026, url
- 234
New Arab (The), Islamic State claims responsibility for assassination of Shia cleric in Syria, 8 May 2026, url; AP, Syrian intelligence agency says it thwarted a planned Islamic State attack on a Shiite shrine, 11 January 2025, url
- 235
UN Security Council, Thirty-seventh report of the Analytical Support and Sanctions Monitoring Team submitted pursuant to resolution 2734 (2024) concerning ISIL (Da’esh), Al-Qaida and associated individuals and entities, S/2026/44, 4 February 2026, url, para. 50
- 236
UN Human Rights Council, Report of the Independent International Commission of Inquiry on the Syrian Arab Republic (A/HRC/61-62), 12 March 2026, url, para 25
- 237
UN Human Rights Council, Report of the Independent International Commission of Inquiry on the Syrian Arab Republic (A/HRC/61-62), 12 March 2026, url, para 100
- 238
SANA, Syrian security forces arrest 12 ISIS members in eastern Syria, 15 March 2026, url
- 239
USDOD, Operation Inherent Resolve And Other U.S. Government activities related to Iraq & Syria, July 1, 2025 – December 31, 2025, 17 February 2026, url, p. 13; US, CENTCOM, U.S., Syrian Forces Locate and Destroy ISIS Weapons Caches in Southern Syria, 30 November 2025, url
- 240
USDOD, Operation Inherent Resolve And Other U.S. Government activities related to Iraq & Syria, July 1, 2025 – December 31, 2025, 17 February 2026, url, p. 13
- 241
ISW and CTP, Iran Update, February 12, 2026, 12 February 2026, url
- 242
UN Human Rights Council, Report of the Independent International Commission of Inquiry on the Syrian Arab Republic, A/HRC/61/62, 12 March 2026, url, para. 22