A U.S. official says police in Washington will announce charges against 12 Turkish security agents related to violence that happened when Turkey's president visited last month.

The official says seven will be charged with felonies. D.C. police will announce charges against five for misdemeanors.

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The official wasn't authorized to speak publicly on the matter ahead of Thursday's announcement and demanded anonymity.

Washington's mayor and police chief have scheduled a news conference to provide an update on arrests.