Turkish President Recep Tayyip Erdogan was reportedly furious at the decision by American authorities to charge several of his nbodyguards with assault.
Back in May, a group of 19 people - among them 15 Turkish security guards and bodyguards - were arrested on suspicion of attacking a peaceful Kurdish demonstration in Washington DC.
The incident was reported to have taken place in front of the Turkish embassy, with 12 reported to be wounded. Three of the group - Muhsin Kose, Yusuf Ayar and Harrettin Eren - have been indicted.
This has infuriated the Turkish President. In a televised statement, Erdogan attacked the charges against the trio, saying it was a "scandalous demonstration of how the American justice system works."
The Turkish Foreign Ministry has made clear it reserves the right to take action against these "unfounded" charges.