The diplomatic incident has sparked outrage in Washington and even prompted the State Department to summon the Turkish ambassador.
The incident occurred after Erdogan arrived after a White House meeting with President Donald Trump.
While it's understandable that his security detail might over-react if it perceived a serious threat to Mr. Erdogan's safety that doesn't excuse criminal acts.
The YPG is the Syrian branch of the Turkish Kurdish Workers Party, the PKK, a Marxist group that has been trying since 1984 to carve out a separatist state from Turkey.
In their Oval Office meetings Tuesday, Trump did not mention Erdogan's increasingly tight grip on power in Turkey or allegations of irregular elections under his leadership. We said: if there is YPG there, we will not take part in it, you yourself will conduct the operation.
"A few police officers stood between us", Flint said. The Secret Service said it plans to work with the police and the State Department "to aggressively pursue accountability for those involved in yesterday's protests".
"After the police line broke, all fought with each other no matter if they were officially on duty or civilian", said the observer.
The Associated Press says they spoke with a congressional aide, who was not authorized to speak publicly and requested anonymity to discuss the situation.More news: Jose Mourinho plans to rest Manchester United players against Arsenal
Determining whether Tuesday's violence would be considered an official duty of the presidential security detail is likely to be a topic of debate between the USA and Turkish governments.
He accused McGurk, the presidential envoy for the global coalition against IS, of carrying on Obama-era policies.
Turkey insists that these YPG militants and their PYD political party are tied to the Kurdish insurgency in Turkey known as the PKK, which the United States of America, the European Union and Turkey all consider a terrorist organization. "It would be beneficial if this person is changed", Cavusoglu said.
US Senator John McCain condemned the attack and called on Trump to react. Such actions may be the norm under Erdogan's repressive regime, but they must not be tolerated in the U.S.
The Turkish security officials were briefly detained at the site of the protest by US law enforcement for their role in the altercation.
The violent capstone to Erdogan's visit spoke to the sky-high tensions between the USA and Turkey, NATO allies that have increasingly sparred over US strategy toward defeating IS militants in Syria. The death toll includes almost 400 civilians.
The statement added that, "Turkey is a key NATO Ally that faces legitimate domestic security concerns emanating from ISIS, PKK, and other designated terrorist organizations".