SDF insurgency in Northern Aleppo

By mid-2018, the insurgency was mostly focused on the rural areas[21][23] and Afrin city's outskirts, where the Turkish Air Force targeted guerilla holdouts between May and July.[21][24] In May, the YPG killed the former leader of the Free East Ghouta Police, Jamal al-Zaghloul, who had been tasked with police duties in Afrin, with a mine in al-Basouta, south of Afrin city. Following his death, the YPG stated that "anyone in cooperation with the invasion forces is our target".[25]

• 9 August - The National Front for Liberation clashed with the YPG in Kafr Nabu and Ba'ai in the southern part of the Afrin district near the border with the Idlib Governorate. Four YPG fighters were killed and several light weapons and explosives were seized by the National Front for Liberation. A representative from the National Front for Liberation told journalists that the group had been monitoring the YPG cell for months as the area had seen heightened levels of violence, mainly assassinations targeting fighters and civilians with links to the TFSA by YPG cells active in the region.[26]
• 26 August - The YPG released a video showing the assassination of an al-Rahman Legion commander, Abu Muhammad Al-Shmali, in Babili.[27]

• 23 October - the Gathering of the Eastern Martyrs, a group affiliated with Ahrar al-Sharqiya, posted a video on its Facebook page showing a captured smuggler affiliated with SDF near Manbij, and displayed a number of captured weapons including machine guns and rocket launchers.[28]

• 3 December - Jaysh al-Islam claimed to have foiled an attempted YPG infiltration in northwestern Aleppo, in the town of Deir Mushmush.[29]
• 21 December - the Afrin Liberation Forces (HRE), a pro-YPG insurgent group, was established and released a press statement laying out the group's goals; the group stated that they seek to end the "occupation of their areas" and that they would carry out operations as part of a "justified war" until the region is "liberated". The statement also claimed responsibility for two attacks: one on 18 December involving the detonation of an improvised explosive device (IED) against Turkish soldiers, claiming as many as six men had been injured and killed, and another attack on the same date, the detonation of another IED on forces of the Hamza Division.[30]

• 20 January - an explosion killed and injured dozens in Afrin city. A medical source claimed that the attack resulted in three dead and 12 injured.[31] On the same day, the HRE claimed to have attacked construction equipment belonging to Turkish forces used for building trenches and tunnels, stating that "Jihadist" fighters allied with the Turkish military had been killed during the attack.[32]
• 23 January - two bombings occurred outside the headquarters of Ahrar al-Sharqiya in the town of Rajo in the Afrin district. No group claimed responsibility for the attack. Three members of the group were killed by the bombs.[33]

• 21 February - A car bombing occurred near a hospital in Afrin city during a Syrian National Army parade, pro-YPG media outlets stated that casualties occurred as a result of the bombing.[34]
• 24 February - A member of the Sultan Murad Division was killed by an IED while attempting to dismantle it.[35]

• 8 April - The Turkish military began training allied rebel forces on air landing via helicopters in Afrin in anticipation of possible planned operations against SDF.[36]
• 11 April - Clashes broke out between Turkish backed forces and Kurdish fighters from YPG in northern Aleppo. The Free Syrian Army fired artillery and mortars at YPG lines and heavy machine gun fire was also used. The clashes reportedly came after a series of heightened tension between SDF and Turkey with the Turkish military recently sending reinforcements to Jarabulus and areas near Manbij which is currently under SDF control.
• 12 April - Turkish forces shelled YPG positions near Tell Rifaat. The YPG responded by shelling positions under Turkish and allied rebel control. Russian military police had withdrawn from the location two days before.[37]

• 4 May - Clashes erupted between Turkish and allied Free Syrian Army forces with the YPG over the death of two Turkish soldiers. During the fighting the Free Syrian Army captured three villages in the northern part of the Tell Rifaat Subdistrict from the YPG, and later withdrew.

• 5 August - HRE stated that it attacked and killed 8 fighters belonging to Ahrar al-Sham and Suqour al-Sham at a base near Mare' and injuring another 4, using AK47 rifles and PK light machine guns as well as RPG-7s. On the same day, HRE also stated that it attacked a Hamza Division base near al-Bab, saying that 3 Hamza Division members were killed and 3 were injured.[38]
• 9 August - HRE stated that it has killed 7 Turkish soldiers during an attack on a Turkish military checkpoint.[39]

• 11 October - Two Turkish soldiers were killed by a mortar attack in Azaz, originating from Tel Rifaat during Operation Peace Spring.[40][41]

• 16 November - As part of the November 2019 Syria bombings, a few car bombs detonated near a bus station and a taxi station in Al-Bab, killing at least 19 and injuring around 50 others.[42] Turkey condemned the attack and said the PKK was behind the bombing.[43][44][45]

• 20 March - Clashes at Basuta occur west of Tel Rifaat between the Afrin Liberation Forces and the TFSA. Injuries from Firqat al Hamza were taken to the Military Hospital in Afrin according to a local source.[46]
• 28 April - A bombing in Afrin killed 53 people, including 11 children. Afrin Liberation Forces (HRE) claimed responsibility for the attack. While Turkey blamed the YPG for the attack. According to the head of the British-based Observatory for human rights in Syria, at least six pro-Turkish Syrian fighters were among those killed in the blast with a possibility of increase in the death toll.[47][12] At least 47 people were reported injured, according to Al Jazeera.[48] The explosion was believed to have been caused by the rigging of a fuel tanker with hand grenades, the governor of Hatay province of the neighboring Turkish border stated.[49] Many people, alongside those who got trapped in their cars were burnt to death as a result of the blast, Syrian activists disclosed.[50][51]
• 21 May - A former ISIL commander named Abu Zaki al-Taybani, who was the head of ISIL's military operations in the Hama Governorate was killed by a CJTF-OIR drone strike in Afrin. He had defected to the Syrian National Army and had previously executed several members of ISIL's former off shoot and rival Hayat Tahrir al-Sham prior to defecting to the SNA, and reportedly had over 200 thousand dollars in his vehicle.[52][53]