The State Department is working with Washington, D.C. police and the U.S. Secret Service to identify the bodyguards working for Turkey’s president who beat up protesters outside of the Turkish embassy in Washington, D.C. on Tuesday.

The melee left at least nine protesters injured and generated intense backlash against Turkey’s president, Recep Tayyip Erdogan.

“We will continue to work with our partners at the United States State Department and United States Secret Service to identify and hold all subjects accountable for their involvement in the altercation,” reads a statement from the Washington, D.C. Metropolitan Police Department.

The department said that Tuesday’s violence stands “in contrast to the First Amendment rights and principles we work tirelessly to protect each and every day.”

In a press conference on Wednesday, DC police chief Peter Newsham said that investigators “have a good idea of some of the folks” involved in the violence.

Newsham added that “a diplomatic immunity issue” could arise in the case since registered diplomats are generally protected from prosecution in criminal cases. But Newsham added that “we are going to pursue everything that’s in our legal power” as part of the investigation.

The State Department said in a statement that it is communicating its concern to the Turkish government “in the strongest possible terms.”

We are concerned by the violent incidents involving protestors and Turkish security personnel Tuesday evening. Violence is never an appropriate response to free speech, and we support the rights of people everywhere to free expression and peaceful protest,” State Department spokeswoman Heather Nauert said.

Video footage of the incident shows men wearing suits clashing with a group of about two dozen Armenian and Kurdish protesters who oppose Erdogan, who was in town to visit with President Trump.

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Erdogan had just finished his meeting with Trump when the melee ensued. The authoritarian ruler then went to the ambassador’s residence to meet in a closed session with members of the Atlantic Council, a Washington, D.C. think tank that receives donations from Turkey.

Footage showed that Washington, D.C. police struggled to contain the violence. At least two people were arrested, though it is not clear whether they were supporters or opponents of Erdogan.

Some of the attackers Tuesday were seen kicking protesters in the head, leaving them covered in blood. One man required stitches on his head, and a woman who was beaten underwent a CT scan, a witness told The Daily Caller.

That witness, Aram Suren Hamparian, also captured footage of the attacks. He told The Daily Caller that the pro-Erdogan side appeared to be professional security forces.

“It all took place at once. It was by very capable people. It felt to me, it looked to me like a highly orchestrated attack,” said Hamparian, the executive director of the Armenian National Committee of America.

Hamparian is highly critical of the Turkish government due to its refusal to recognize the Armenian genocide of a century ago.

The actions of Erdogan’s security forces is not a surprise to many observers of Turkish politics. Erdogan has led a nationwide crackdown against critics of his regime. Thousands have been jailed and tens of thousands more have been forced from their jobs, often based on hazy allegations of having ties to terrorist groups.

Erdogan’s bodyguards were involved in a similar incident during a visit to Washington, D.C. last March. The bodyguards verbally and physically assaulted a group of anti-Erdogan journalists outside of an event hosted by the Brookings Institution.

This afternoon in front of the residence of the Turkish ambassador in Washington pic.twitter.com/nb1X3A0prm — Mutlu Civiroglu (@mutludc) May 16, 2017

A social media campaign began on Wednesday to identify the Erdogan bodyguards involved in the brawl. #ArrestErdogansBodyguards features still images of video footage of the bodyguards beating protesters.

Some U.S. lawmakers called out Erdogan following Tuesday’s incident.

Frederick Kempe, the CEO of the Atlantic Council, condemned Tuesday’s violence.

“The Atlantic Council strongly condemns the violence that occurred involving protestors and Turkish security personnel Tuesday evening outside an event that the Council was co-hosting for Turkish President Erdoğan,” Kempe said in a statement.

“The proper authorities will determine what, if any, actions should be taken against those who instigated the violence. Such behavior only detracts from the Council’s foundational mission of promoting constructive US leadership alongside friends and allies to secure the future.”

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