An announcement Friday that the U.S. troop withdrawal from Syria has begun came amid a precautionary buildup of U.S. forces in the region and renewed threats from Turkey about attacking the U.S.-backed Syrian Democratic Forces, or SDF.
The Syrian Observatory for Human Rights, which uses a network of frontline activists to monitor the Syrian civil war, reported that roughly 10 U.S. armored vehicles and several trucks pulled out of the northeastern Syria town of Rmelan on Thursday night and crossed into Iraq.
The Kearsarge Amphibious Ready Group, carrying roughly 2,000 Marines from the 22nd Marine Expeditionary Unit (MEU), is in the Mediterranean to guard against any threats to the withdrawal.
In addition, U.S. warplanes from the aircraft carrier Stennis, patrolling the Persian Gulf, were flying missions over Syria and Iraq, Stars & Stripes reported from aboard the Stennis.
In an e-mail statement to The Associated Press on Friday, Army Col. Sean Ryan, spokesman for Combined Joint Task Force-Operation Inherent Resolve, the U.S. regional command, said the U.S. had begun "the process of our deliberate withdrawal from Syria."
"Out of concern for operational security, we will not discuss specific timelines, locations or troop movements," Ryan said. The AP, citing a U.S. defense official, also reported that the pullout thus far has involved only equipment and not the estimated 2,000 U.S. troops believed to be in Syria.
The beginning of the withdrawal followed Joint Chiefs Chairman Gen. Joseph Dunford's meetings in Ankara on Tuesday with Turkish counterpart Gen. Yasar Guler and Defense Minister Hulusi Akar.
A readout of the meeting from the Joint Staff said that Dunford, Guler and Akar "discussed the security situation in Syria, the completion of the Manbij roadmap [on security cooperation], and the deliberate, coordinated effort to withdraw U.S. ground forces from Syria."
On an inspection of Turkish troops massing at the Syrian border Friday, Akar said preparations are underway for an operation to rout the Syrian Kurdish YPG (People's Protection Units), the main fighting force within the SDF, from Manbij and areas east of the Euphrates River, according to Turkey's state-run Anadolu news agency.
"We have Manbij, and the east of Euphrates ahead," Akar said, echoing threats going back months from Turkish President Recep Tayyip Erdogan and other Turkish officials to mount an operation in Syria against the YPG.
"We have no problems with our Kurdish brothers, Arab brothers in Syria, Turkmens and other ethnic and religious groups. Our only targets are terrorists, Daesh [Islamic State] and PKK/YPG," Akar said. Turkey considers the YPG to be part of the PKK, or Kurdistan Workers Party, a separatist group in eastern Turkey which has been labeled a terrorist organization by Turkey, the U.S. and the European Union.
Turkish Foreign Minister Mevlut Cavusoglu said he will carry out the long-planned offensive against the YPG, regardless of the U.S. withdrawal pace.
"If the [withdrawal] is put off with ridiculous excuses like Turks are massacring Kurds, which do not reflect the reality, we will implement this decision," Cavusoglu told local news station NTV.
In Ankara on Tuesday, Erdogan refused to meet with U.S. National Security Adviser John Bolton, who earlier had appeared to set conditions on the U.S. withdrawal, including the lasting defeat of the Islamic State and guarantees that Turkey would not attack the YPG.
The Syrian Observatory also reported that the SDF is bolstering its forces on the border with Turkey "in anticipation of any surprise attack."
The Kearsarge amphibious ready group (ARG), which includes the 22nd MEU, the amphibious assault ship Kearsarge, the amphibious transport dock Arlington and the dock landing ship Fort McHenry, entered the 6th Fleet's area of operations, including the Mediterranean, last month.
"Teaming with the Kearsarge ARG, we look forward to training with allied and partner military forces while also providing versatile, amphibious response options to our combatant commanders as we face myriad global challenges," Col. Michael Perez, commander of the 22nd MEU, said in a statement last month.
U.S. President Donald Trump announced via Twitter on Dec. 19 that all U.S. troops in Syria would come home.
Trump initially indicated that the withdrawal would be quick but has since stated that it would be "slow and coordinated" with allies.
The day after Trump's tweet, Defense Secretary Jim Mattis resigned, saying that Trump as commander-in-chief deserved a defense secretary whose views are "better aligned" with his own.
The planned withdrawal of U.S. forces and possible repercussions adds to the turmoil in a region embroiled in a seven-year-old civil war that has displaced millions and killed at least 400,000 through 2016, according to the most recent United Nations estimate.
Of the nearly 5.2 million registered refugees from the Syrian civil war, more than 3.5 million are in Turkey, according to the United Nations High Commissioner for Refugees.
With the backing of Russia and Iran, Syrian President Bashar al-Assad has regained much of the territory lost to rebel groups, and his forces are now pressing eastward to areas controlled by the SDF.
In Moscow on Friday, Maria Zakharova, a Russian Foreign Ministry spokeswoman, expressed doubt that the U.S. would continue with its withdrawal, according to Russia's Interfax news agency.
She charged that the U.S. appeared to be "looking for a reason to stay" in Syria. In response to questions, she said, "I cannot share your confidence that they are leaving there because we never saw an official strategy."
-- Richard Sisk can be reached at Richard.Sisk@Military.com.