ANKARA, Turkey: The Latest developments in the civil war in Syria (all times local):
A Syrian activist group monitoring the civil war says Syrian rebels who were amassed at the Turkish border have crossed into Syria as part of a Turkey-backed operation to liberate an Islamic State-controlled border town.
The Syrian Observatory for Human Rights says the fighters were preceded by Turkish tanks and mine sweepers that crossed into Syria earlier on Wednesday as part of the operation to clear Jarablus from IS militants.
The Britain-based monitoring group didn't say how many fighters were involved. On Tuesday, it said that around 500 rebels were waiting to cross into Syria.
Turkish state media, meanwhile, say the rebels were about to enter a Syrian village leading to Jarablus.
Turkey's state-run news agency says Turkish tanks have crossed into Syria as part of a military operation to free a border town held by the Islamic State group.
In its report, Anadolu Agency, which cited unnamed government officials, did not say how many tanks had entered Syria.
Turkeys' private NTV television says as many as 20 tanks had crossed into Syria. It said clashes were taking place at the border.
Vice President Joe Biden has arrived in Ankara for talks with Turkish leaders as Turkey launched a military operation to clear a Syrian border town of Islamic State militants.
Wednesday's visit comes at a difficult time for ties between the two NATO allies.
Turkey is demanding that Washington quickly extradite a U.S.-based cleric blamed for orchestrating last month's failed coup. The United States is asking for evidence against the cleric and asking that Turkey allow the extradition process to take its course.
In Syria, Turkey is concerned about the growing power of U.S.-backed Syrian Kurdish forces, who it says are linked to Kurdish groups waging an insurgency in southeastern Turkey.
Wednesday's operation puts Turkey on track for a confrontation with the Kurdish fighters in Syria.
Biden is scheduled to meet with Turkish President Recep Tayyip Erdogan and Prime Minister Binali Yildirim.
Turkish Interior Minister Efkan Ala says Turkey launched the operation to free the IS-held Syrian town of Jarablus to safeguard its own security.
The minister says Turkey "cannot sit and watch" and that "it is Turkey's legal right, it is within its authority" to take action.
The minister added that Wednesday's operation aimed to support the moderate Syrian opposition and is being carried out in coordination with the U.S.-led coalition forces. He said he hoped the operation to clear Jarablus would be completed at the soonest, but did not provide a time-frame.
About the operation's duration, he says: "Until when? Until this threat is removed and the terror threat on our border disappears."
Ala also says that his country "will not provide the opportunity for terror organization to threaten Turkey from across the border," adding that the Turkish town of Karkamis, across the border from Jarablus, had been hit by nine mortar rounds on Tuesday and another round on Wednesday.
A Turkish media report says a small number of Turkish special forces have crossed into Syria as part of a Turkish operation to rid a Syrian border town of Islamic State group militants.
Private NTV television says the Turkish special forces entered Syria on Wednesday in what it described was an "intruder mission" to carry out "pinpoint operations" against IS as part of the mission to clear the town of Jarablus of the extremists.
The London-based Syrian Observatory also said the Turkish troops had entered Syria.
Turkish government officials could not immediately confirm the report.
Turkey's and the U.S.-backed coalition forces on Wednesday launched an operation to clear a Syrian border town from Islamic State militants, the office of the Turkish prime minister said.
The operation began at 4 a.m. (0100 GMT), with Turkish artillery launching intense cross-border fire on the town of Jarablus, followed by Turkish warplanes bombing IS targets in the town, the state-run Anadolu Agency reported.
It was not immediately clear if any Turkish or Turkish-backed Syrian opposition forces crossed the border to take part in the operation.
The news agency said the operation aims to clear Turkey's border of "terror organizations" and increase border security, as well as "prioritize and support" Syria's territorial integrity. The assault followed Turkish Foreign Minister Mevlet Cavusolgu pledge on Tuesday of "every kind" of support for operations against IS along a 100-kilometer (62-mile) stretch of Syrian frontier.