Sinem Mohamed, the USA representative of the Democratic Federation of Northern Syria Representative (DFNS), made those comments on Monday, a day after the Kurdish administration reportedly accused Russia of backing Turkey's attack on Afrin.
"Syrians fleeing to the Turkish border seeking safety and asylum are being forced back with bullets and abuse", said Lama Fakih, deputy Middle East director at Human Rights Watch.
Turkey's Western allies, including the United States, do not classify the YPG as a terror group and have worked closely with its fighters in the battle against Islamic State militants.
Five Turkish soldiers were also wounded in operations inside Syria yesterday, the army said in a statement.
Meanwhile, seven Turkish soldiers have been killed.
Turkey shares a 566-mile border with Syria and the YPG (People's Protection Units) controls much of the Syrian side.More news: Ideal 2018 release to create massive sales boost
Three Turkish soldiers were reported killed in the offensive earlier in the day, putting the total death toll for Turkish troops since the operation started on January 20 at 14.
However, Turkey considers the US-backed Syrian Kurdish group a terrorist organisation, a growing power on its southern border which threatens its security. Mr. Bozdag went further, adding that USA forces could be targeted by Turkish troops moving into Manbij if they are spotted wearing YPG "uniforms".
Turkey considers the Kurdish YPG, which is backed by the USA, to be a terrorist group and an extension of the Kurdistan Workers Party (PKK).
A Syrian militant in the area said the Russian pilot was shot and killed when he resisted capture. "You allow them to settle and tell us 'Don't come to Manbij.' We will come to Manbij to hand it over to its real owners", Erdoğan told his ruling Justice and Development Party's (AKP) parliamentary group on February 6.
'And then you tell us not to come to Manbij!