A Syria war monitor said Friday that Turkish drone strikes had killed 27 civilians in Syria in a 24-hour military escalation, following a deadly attack on a defence company near Ankara.
Turkish forces had "dramatically escalated their aerial and ground attacks in north and east Syria" since Thursday, said the Syrian Observatory for Human Rights.
The monitor added that it documented 45 drone strikes and four by fighter jets targeting infrastructure, including water, power and gas stations.
Turkey launched air strikes on Kurdish fighters in Iraq and Syria on Wednesday, blaming them for an attack that claimed five lives at a defence firm near the Turkish capital.
A further 22 people were wounded in the attack, which the government said was "very likely" carried out by the outlawed Kurdistan Workers' Party (PKK).
Hours later, "an air operation was carried out against terrorist targets in the north of Iraq and Syria," the defence ministry said in a statement.
"A total of 32 targets belonging to the terrorists were successfully destroyed."
The Kurdish-led Syrian Democratic Forces said in a statement Thursday that Turkish air strikes killed 12 civilians in northeastern Syria and wounded 25 others.
"In addition to populated areas, Turkish warplanes and UAVs (drones) targeted bakeries, power stations, oil facilities and (Kurdish) Internal Security Force checkpoints," the SDF added, also reporting Turkish shelling.
The US-backed SDF spearheaded the campaign that dislodged Islamic State group jihadists from their last scraps of Syrian territory in 2019.
Turkey sees the Kurdish People's Protection Units (YPG), which dominate the SDF, as an offshoot of the PKK.
Turkish troops and allied rebel factions control swaths of northern Syria following successive cross-border offensives since 2016, most of them targeting the SDF.