WATCH: Erdogan Observes, Possibly Orders Assault on DC Protesters

The video depicts the exterior of the Turkish embassy, with a shot of car bearing the presidential seal of Turkey, while protesters chant "Baby Killer Erdoğan" in the background. A man leans into the car, speaking to someone in the backseat. The same man then straightens up and speaks to a mustachioed man standing nearby. The mustachioed man nods and dashes away.

A few seconds later, the chants abruptly end. The protest rapidly dissolves into a street fight.

​A wall of black-suited security officials form to separate the car from the violence. Forty seconds later, Erdoğan emerges from the backseat of the car and briefly watches the melee unfold before his eyes. With little expression, he then turns around and starts walking to the embassy. The mustachioed man from earlier returns and briefly exchanges words with Erdoğan.

The confrontation, in which nine people were injured, is proving to be diplomatically uncomfortable for the US State Department, which promised to conduct a "thorough investigation that will allow us to hold the responsible individuals accountable," saying that doing so "is of the utmost importance to us." 

​The State Department announced that they had placed two of Erdoğan's bodyguards in custody after the incident, but then released them in short order. "Customary international law affords heads of state and members of their entourage with inviolability from arrest and detention," a State Department official told CNN. "The United States recognizes this inviolability, which provides reciprocal protection for the United States abroad."

Diplomats and their entourages are guaranteed legal immunity in their host countries, with the implicit understanding that a diplomat who breaks the law will be duly punished in their home country, or their immunity will be waived if their crime is serious enough.

But what happens if the malfeasance is done at the direct order of that country's president? Although there is no direct evidence that Erdoğan ordered his men to attack, the video certainly suggests it.

"Groups affiliated with the PKK [the Kurdistan Workers' Party], which the US and Turkey have designated as a terrorist organization… began aggressively provoking Turkish-American citizens who had peacefully assembled to greet the President," read a statement from the Turkish embassy on Wednesday.

"The violence and injuries were the result of this unpermitted, provocative demonstration. We hope that, in the future, appropriate measures will be taken to ensure that similar provocative actions causing harm and violence do not occur."

Congressmen including Arizona Republican Senator John McCain called for Turkish Ambassador to the US Serdar Kilic to be ejected from the country. "We should throw their ambassador the hell out of the United States of America," said McCain during an appearance on Morning Joe, an MSNBC talk show. "This kind of thing cannot go un-responded to diplomatically,"