Rebels backed by Turkish forces claim they have made major gains against fighters allied to the Kurds in northern Syria.
Kurdish fighters have been expelled from several towns and villages, according to the rebels, as part of an escalating campaign by Ankara.
Among the villages Turkish-backed rebels have seized from Kurdish aligned forces is al Amarna, where fighting has been described as fierce over the past few days.
It came as Sky News filmed the first images of Turkish tanks operating in Syria.
Turkey’s military claimed it had killed 25 Kurdish militants in airstrikes in northern Syria.
The militants were said to have been killed around Jarablus, a Syrian town on the border that Turkish tanks and special forces crossed into last week, to remove Islamic State from the town.
The mostly-Kurdish People’s Protection Units, or YPG, are backed by the US and UK.
Aided by US-led coalition airstrikes, the YPG has been the most effective group so far in restricting the advance of IS in Syria.
The fighting between them and Turkish-supported rebels and Turkish tanks and jets pits Turkey against its NATO allies.
Turkish President Recep Tayyip Erdogan said his military is committed to fighting terrorism in Syria and Iraq but is also determined to “uproot” the Syrian Kurdish group, which he called a terrorist organisation.
Turkish leaders have vowed to drive both IS and the YPG away from the border, but Mr Erdogan didn’t specify a goal.
A spokesman for the Turkish-backed Syrian rebels said the offensive will continue with the aim of clearing IS and Kurdish forces from northeastern Aleppo.
A captain with the Turkish-backed Syrian rebels said the aim was to push the YPG back to the east bank of the Euphrates river, a position the US has agreed they should occupy.
The Turkish army said it was taking all the measures it could to avoid any civilian deaths in Syria but the Syrian Observatory for Human Rights monitoring group said at least 35 civilians were killed south of Jarablus.
It said 20 people died in strikes on Jeb el Kussa, and another 15 were killed in a separate bombardment near al Amarna.
Four local fighters were also killed, the UK-based Observatory reported.
Spokespeople representing the Kurdish authorities in Syria have claimed there are no Kurdish forces in the villages where the fighting has been raging.
On Friday night, the YPG said Turkey’s military had fired on a village near Kobani, about 20 miles east of Jarablus.
And it said Turkey had also used heavy weapons to fire on YPG positions in the northwestern province of Afrin, about 65 miles west of Jarablus.
Turkey wants to stop Kurdish forces taking control of a line of territory along its southern border, fearing it could be used by Kurdish militants from the PKK, which has been waging an insurgent war in southeast Turkey for decades.
On Saturday, there were reports that suspected Kurdish militants fired four rockets at Diyarbakir Airport in southeast Turkey.
There were no casualties and Diyarbakir governor Huseyin Aksoy said there was no disruption to flights.