Updated

Nineteen people, including 15 Turkish security officials, have been indicted for attacking protesters during a visit to the U.S. from Turkish President Recep Tayyip Erdogan, in a massive brawl caught on video.

Witnesses to the scuffle outside the Turkish Embassy in Washington, D.C., in May claimed that members of Erdogan's security detail attacked the demonstrators. Erdogan was in the U.S. for a meeting with President Donald Trump at the time.

Two Turkish bodyguards were briefly detained after the incident. They later were set free and returned to Turkey.

The indictments charged the defendants with attacking peaceful demonstrators who were protesting Erdogan's visit on May 17. All 19 were charged with conspiracy to commit a crime of violence, a felony punishable by a maximum of 15 years in prison.

Several face additional charges of assault with a deadly weapon.

Recep Tayyip Erdogan

Turkey's President Recep Tayyip Erdogan with U.S President Donald Trump in the Oval Office of the White House, May 16, 2017. (REUTERS)

Sixteen of the defendants had already been charged June 13 but Tuesday's indictment added three new defendants, all Turkish security officials. Two of the defendants were arrested in June and face an initial court hearing on Sept. 7.

The rest remain at large.

The U.S. ambassador in Ankara, John Bass, was later summoned to the Ministry of Foreign Affairs, Turkey said, over what it called "aggressive and unprofessional actions" by U.S. security personnel against Turkish bodyguards in Washington during Erdogan's visit.

"We can confirm the Turkish Foreign Ministry convoked our Ambassador to Turkey to discuss the violent incidents involving protestors and Turkish security personnel on May 16," State Department spokeswoman Heather Nauert said at the time. "As we noted previously, the conduct of Turkish security personnel last week was deeply disturbing. The State Department has raised its concerns about those events at the highest levels."

The Associated Press contributed to this report.