Turkey's military says it has taken control of a key Syrian border town as Ankara presses ahead with its offensive against Kurdish fighters despite facing mounting international criticism over the operation.
The Turkish defence ministry said its troops seized Ras al-Ain from the Kurdish-led Syrian Democratic Forces (SDF) on Saturday - a claim that was immediately rebutted by the SDF - as fighting between the two sides entered its fiercest phase since Ankara launched its offensive on Wednesday.
"As part of the successful operations being conducted in the framework of Operation Peace Spring, the town of Rasulayn, located east of the Euphrates, has been brought under control," the ministry said in a post on Twitter.
But the SDF said Turkish troops had only entered one neighbourhood in Ras al-Ain's industrial district after hours of heavy shelling had pressed its own forces into a "tactical retreat" from that area.
Turkish fighter jets and heavy artillery units have bombarded Ras al-Ain - one of two key border towns targeted in Ankara's offensive, alongside Tal Abyad - for days.
Al Jazeera’s Charles Stratford, reporting from Akcakale on the Turkey-Syria border, said there had been reports of "clashes in surrounding villages" following the competing claims over control of Ras al-Ain.
"There has also been more heavy shelling on and around Tel Abyad today," he added.
Across the region, Turkish troops and allied Syrian rebel fighters have made gains, capturing several northern villages in fighting that has left dozens killed or wounded and forced more than 100,000 people to flee their homes since Wednesday.
Meanwhile, markets, schools and hospitals have been closed, according to the United Nations, with aid agencies warning nearly a half-million people are deemed to be at risk.
The Turkish ground and air assault began three days after US President Donald Trump announced that his country's troops would be withdrawn from their border positions alongside the SDF, the main ally of Washington in the fight against ISIL and a group that expanded its control in northern and eastern Syria amid the chaos of the country's eight-year civil war.
Trump's decision drew swift domestic and international criticism that he was endangering regional stability, abandoning US allies and risking the revival of ISIL.
Amid the heavy fighting on Saturday, the SDF called on its "allies" to carry out their "moral responsibilities" and impose a no-fly zone in a rebuke seemingly aimed at Washington.
"This is something they can do easily," SDF spokesman Redur Xelil said in a statement, adding Turkey's offensive had "revived" the threat posed by ISIL.
"We are now fighting on two fronts: one front against the Turkish invasion and a front against Daesh," he said.
The SDF holds most of the northern Syrian territory that once made up part of ISIL's self-proclaimed "caliphate", and has been keeping thousands of suspected fighters from the armed group in jails and tens of thousands of their family members in camps.
The developments have been accompanied by rising disapproval over Turkey's cross-border offensive, with Trump's administration warning the operation was causing "great harm" in relations with its NATO ally and threatening to impose sanctions on Ankara.
Germany and France, other fellow NATO allies, said on Saturday they were banning some arms exports to Turkey, while the head of the 22-member Arab League called for the United Nations Security Council to take measures to force Turkey to halt its "invasion".
Turkish President Recep Tayyip Erdogan has dismissed criticism of the operation, however, saying on Friday that Turkey "will not stop" the offensive "no matter what anyone says".
He says the move is aimed at creating a so-called "safe zone" freed of the Kurdish fighters within which some of the 3.6 million refugees currently residing in Turkey can be resettled.
Ankara views the main fighting element of the SDF - the Kurdish People's Protection Units (YPG) - as an extension of the outlawed Kurdistan Workers' Party (PKK) and wants to drive the forces further away from its border with Syria.
Turkey on Saturday said 459 YPG fighters had been "neutralised" since the operation began, a term that commonly means killed. The Kurds disputed the figure, saying 29 of its fighters were dead. Four Turkish soldiers have also been killed since the beginning of the offensive, including two who were killed in Syria's northwest.
Despite the rising bloodshed, Turkish Foreign Minister Mevlut Cavusoglu dismissed an offer by US President Donald Trump to mediate between Ankara and YPG forces.
"We don't mediate, negotiate with terrorists. The only thing to be done is for these terrorists to lay down arms," Cavusoglu told German broadcaster Deutsche Welle.
"We tried the political solution in Turkey in the past and we saw what happened," he added.
From Akcakale, Al Jazeera's Stratford said Turkish "armoured personnel carriers, tanks and heavy military equipment" had continued "pouring towards the border".
"Despite increasing international condemnation, there is no sign whatsoever of the Turkish military pulling back," he added.
SOURCE: Al Jazeera and news agencies