A day after a protest at the Turkish ambassador's residence in Washington, D.C., turned violent, the State Department is criticizing Turkey's government.

Video appears to show security forces belonging to Turkish President Recep Tayyip Erdogan pushing past police and violently breaking up the demonstration.

Some of the protesters were knocked down and kicked repeatedly in the head. Nearly a dozen people were injured.

Investigators with the Metropolitan Police Department are working with the Secret Service and the State Department to identify the people on the videos.

The State Departmentissued a statement about Tuesday's melee:

"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."We are communicating our concern to the Turkish government in the strongest possible terms."

It's not clear to what extent President Erdogan's full security team was involved.

"It's part of an unfortunate theme that surrounds many of his overseas trips," says Ishaan Tharoor, a foreign affairs writer for The Washington Post.

Tharoor talked to NPR's Audie Cornish during Wednesday's All Things Considered.

"Just last year, when Erdogan was back in the States for a summit on nuclear security, at Brookings, outside Brookings, [in Washington, D.C.], there were similar protests and similar unseemly scenes of clashes along Massachusetts Avenue. There have been incidents involving his security detail in Ecuador. And in general, Erdogan is a figure who presides over profound political polarization back home."He has, in many senses, further deeply divided Turkey and builds his politics on a kind of very vehement nationalism that leads to these kinds of scenes among the diaspora overseas. And at the same time, of course, he is somebody who survived a coup attempt last year. So for him, and presuming for a security detail, opposition and especially vocal opposition — they don't take it very lightly."

Two men were arrested at the scene, and police intend to pursue charges against others involved, the Metropolitan Police Department said in a statement on Wednesday:

"The actions seen outside the Turkish Embassy yesterday in Washington, D.C. stand in contrast to the First Amendment rights and principles we work tirelessly to protect each and every day," the police statement said. "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."

The Turkish Embassy in a statement blamed the violence on the demonstrators:

"Groups affiliated with the PKK, which the U.S. and Turkey have designated as a terrorist organization, gathered yesterday without permit in Sheridan Circle in the immediate vicinity of the Ambassador's Residence, while the President of Turkey was visiting the Residence."The demonstrators began aggressively provoking Turkish-American citizens who had peacefully assembled to greet the President. The Turkish-Americans responded in self-defense and one of them was seriously injured."

The U.S. announced last week that it would arm Kurdish fighters in Syria, a move Erdogan is against because he says they are linked to the Kurdish insurgency in Turkey known as the PKK.

Erdogan met President Trump at the White House on Tuesday, and during that meeting he made it clear that the decision to arm the group will "never be accepted."

The meeting between the two leaders happened hours before the demonstration turned violent.

An attorney for Ayten Necmi, 49, one of the protesters who was arrested, told The Washington Post that he blamed D.C. police and the Secret Service for "being surprised" by the large turnout and overreacting.

Protest organizer Seyid Riza Dersimi, 61, told The Post that he was injured in the violence and needed stitches.

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