Turkey sent more tanks into northern Syria on Saturday, Syrian opposition sources said, as rebels backed by Ankara said they were moving to seize the last stretch of territory held by Islamic State on the Syrian side of the border.
Sources close to Turkish-backed rebel groups, who asked not to be quoted by name, said that the rebels had captured three villages west of the border town of Jarabulus and another three villages near the border village of al-Rai from Islamic State jihadists.
A military commander in the Turkish-backed rebel Sultan Murad Brigades said that the operations aimed at capturing the last stretch of the border held by Islamic State, which lies between the two locations.
The Turkish border is the jihadist organization's only direct link between its territories in Syria and Iraq and the outside world. It has used it in the past to bring in foreign fighters joining its forces.
The group has been expelled from most of the border region over the past 18 months by Kurdish-led Syrian forces, backed by US-led airstrikes.
The commander in the Sultan Murad Brigades said Turkey had sent ten tanks and three armoured personnel carriers to back up the rebels, a force he said was sufficient to help them seize that last border region.
The Syrian Observatory for Human Rights, a monitoring group, said that Turkish tanks had been seen near al-Rai. It also confirmed the rebel capture of at least three villages west of Jarabulus.
Turkey's state-run Anadolu news agency reported that Turkish troops and armoured vehicles had again pushed into Syrian territory north-east of Aleppo to back up rebel forces.
Turkey launched a military operation in Syria late last month, sending hundreds of Syrian rebels backed by its own tanks and airstrikes across the border to capture Jarabulus from Islamic State.
They seized the town quickly but then turned their attention on the Kurdish-led forces that have battled Islamic State across northern Syria, drawing a sharp rebuke from the United States.
Turkish President Recep Tayyip Erdogan said that the Syrian operations were aimed at both Islamic State and the Kurdish forces, which Ankara describes as terrorists due to their links with banned Kurdish rebels operating on Turkish soil.
Since Tuesday the Turkish-backed rebels have once more moved against Islamic State, and an undeclared truce appears to be holding with the Kurdish-led forces, who withdrew south of the Sajur river some 15 kilometres from the border.
Turkish tanks also returned to a Kurdish-held city further east in Syria, a day after local protesters forced them to retreat, the Observatory reported.
The tanks and military vehicles pushed for several metres into Kobane near the Turkish border, where two civilians, including a child, were killed and dozens injured on Friday when Turkish forces shot at protesters, the monitoring group said.
Residents in the city have staged protests since August 27 against Turkey’s construction of a cement separation wall at the border with Kobane, according to the observatory and Kurdish officials.
There was no immediate official comment on the Kobane operations in Ankara.
Kobane was the site of the first significant victory over Islamic State when Kurdish forces, backed by US-led air power, recaptured the city from the radical group in January 2015.