"Over the past hours... a new wave of (Turkish) attacks on northern and eastern Syria" killed "12 civilians, including two children", and wounded 25 others, a statement from the US-backed force said.

"In addition to populated areas, Turkish warplanes and UAVs (drones) targeted bakeries, power stations, oil facilities and (Kurdish) Internal Security Force checkpoints," the statement added, also reporting Turkish shelling.

Turkey launched air strikes on Kurdish militants in Iraq and Syria Wednesday blaming them for an attack that killed five people at a defence firm near Ankara.

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 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 swathes of northern Syria following successive cross-border offensives since 2016, most of them targeting the SDF.