Turkish tanks, supported by Syrian opposition rebels, have stormed across the border into northern Syria, within hours seizing the town of Jarablus that Islamic State jihadists had controlled since 2014.
"Jarablus is completely liberated," declared Ahmad Othman, commander of the Sultan Mourad rebel group.
Turkey's state news agency also confirmed the takeover. The British-based Syrian Observatory for Human Rights said Islamic State fighters put up "very little resistance" before fleeing to neighboring villages in the face of the Turkish onslaught.
It was the first time since Islamic State has claimed a caliphate straddling parts of Iraq and Syria two years ago that it had given up territory within hours after fighting began for control of a town.
The lightning quick offensive, which Ankara said was aimed at clearing Islamic State militants and Syrian Kurds from the border region, was Turkey's most significant involvement so far in the five-year Syrian conflict.
American warplanes, A-10s and F-16s, launched airstrikes in support of Turkish and Syrian opposition operations against Islamic State targets in Jarablus. "We want to help the Turks get ISIL off the border," one official said, using an acronym for Islamic State.
About 1,500 Syrian opposition fighters joined the cross-border operation. In a pre-dawn start to the fighting, Turkey fired artillery shells at Islamic State targets, with Turkish and U.S. fighter jets hitting IS strongholds near Jarablus, with the rebels first capturing the nearby IS-held village of Kaklijeh.
Islamic State territorial losses between January 2015 and July 2016 (IHS Conflict Monitor)
Turkish President Recep Tayyip Erdogan said the offensive was in response to a series of attacks in Turkey, including the suicide bombing of a Kurdish wedding party near the border last weekend that killed 54 people. He said the goal was to end threats from "terror" groups, Islamic State jihadists and U.S.-backed Syrian Kurdish militia linked to Turkey's outlawed Kurdish rebels.
But Turkey's targeting of the Syrian Kurds could put it on track for a confrontation with U.S. military operations in Syria. Washington considers the Kurdish rebels in Syria to be the most effective fighters against Islamic State jihadists, even as Ankara has waged a three-decade fight against Kurds who are seeking an autonomous state in southeastern Turkey.
Vice President Joe Biden, who met Wednesday with top officials in Ankara, told a news conference the U.S.-backed Kurdish rebels must remain east of the Euphrates River in Syria, keeping the forces far from Turkey's border.
Turkish Prime Minister Binali Yildirim (R) as US Vice President Joe Biden waves as they pose for a photograph before their meeting at Cankaya Palace in Ankara, Aug. 24, 2016.
"They cannot, will not and under no circumstances get American support if they do not keep that commitment. Period," Biden said.
Syria's Foreign Ministry condemned Turkey's actions as a violation of its sovereignty.
Russia's Foreign Ministry expressed deep concern about the operation, especially Turkey's targeting of Kurdish militia fighters. It said that Turkey, by targeting both Islamic State militants and Syrian Kurds, could further inflame the Syrian civil war, leading to "flare-ups of inter-ethnic tensions between Kurds and Arabs."
Wednesday's operation came a day after Foreign Minister Mevlut Cavusoglu said Turkey would give "every kind" of support to fighting Islamic State in the area around Jarablus. On Monday, the government vowed to "cleanse" Islamic State following the wedding suicide bombing in nearby Gaziantep.
Islamic State controlled a long stretch of the Turkey-Syria border in early 2015, but Kurdish fighters have regained a large portion of the territory, particularly to the east of Jarablus.
Denying the militants access to the border cuts off a potential route for supplies and bringing in fighters, but Turkey has been wary of those gains being accompanied by the Kurds expanding their control in northern Syria.
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