Turkish tanks rolledinto northern Syria as part of a major operation aimed at wiping out ISIS militants, Turkey's foreign minister announced Wednesday.
The incursion — which also involves special forces — came hours after Turkish jets started pounding targets in northern Syria and shortly before Vice President Joe Biden's arrival in the country for a planned visit.
State-run Anadolu news agency reported that the Turkish Armed forces had hit 81 targets since the assault began at around 4 a.m. (9 p.m. ET).
Turkey's Foreign Minister Mevlut Cavusoglu later said that Turkish tanks and Syrian opposition forces were in the city of Jarabulus, some 3 kilometers (1.9 miles) inside Syria.
Turkey's state-run news agency and a Syrian opposition activist said the forces had also captured the village of Kaklijeh, The Associated Press reported.
In a televised speech broadcast live, President Recep Tayyip Erdogan said the operation — dubbed "Euphrates Shield" — was aimed at diminishing the threat of "terror" groups like ISIS and a Syrian Kurdish militia.
The offensive also "aims to support U.S.-led coalition forces" and strengthen Turkey's border security, military sources told Anadolu.
The Syrian government called the incursion a "blatant violation" of the government's sovereignty, and accused the United States of providing air support for Turkish military, according to the AP.
A U.S. defense official confirmed to NBC News that that coalition aircraft were conducting air strikes in support of Turkish and Syrian opposition operations against ISIS in Jarabulus.
There was no immediate comment from U.S. officials, but all eyes were on Biden to see if he would weigh in on the offensive — the NATO member's most significant so far in the the Syria conflict — while in Ankara on Wednesday.
Biden is the most senior U.S. official to travel to the country since a failed July 15 coup strained ties between the two NATO members and shook confidence in Turkey's ability to step up the fight against ISIS.
Wednesday's operation also follows a series of deadly attacks that Turkish officials have blamed on ISIS — including a suicide bombing that killed 54 people at a wedding near the border.
Angered by a perceived lack of Western sympathy over the coup, Turkey has increasingly cozied up to Russia and proposed more military cooperation with Moscow in fighting ISIS — a worrying prospect for some of Turkey's Western allies.
The offensive launched Wednesday put Turkey on track for a possible confrontation with U.S.-backed Kurdish fighters, who have been the most effective force against ISIS in northern Syria.
Ankara is worried about the growing influence and power of the group, which it claims has links to Kurdish insurgents in southwestern Turkey.