The Trump administration faced growing calls Thursday for a forceful response to violence by Turkish presidential guards on American soil, who were briefly detained this week but then set free. The unseemly incident added to U.S.-Turkish tensions that are being compounded by a growing spat over U.S. war strategy against the Islamic State group in Syria. The United States said it summoned Turkey's ambassador to the State Department, where the No. 2-ranked U.S. diplomat raised concerns about the security detail for President Recep Tayyip Erdogan's visit to Washington, after they were captured on video violently breaking up a protest. U.S. lawmakers demanded stronger action. The government should "throw their ambassador the hell out" of the country, Republican Sen. John McCain said. The calls came as the administration conceded it had released two members of Erdogan's detail after holding them briefly after the incident, which took place outside the Turkish ambassador's residence in the U.S. capital on Tuesday. While officials vowed an investigation, the guards are already safely back in Turkey with Erdogan, dampening any prospects for holding them accountable.

Local police and lawmakers initially speculated that diplomatic immunity prevented the U.S. from holding the men. A U.S. official said Thursday that wasn't the case. Instead, Erdogan's guards were released under a globally recognized custom under which nations don't arrest or detain visiting heads of state and members of their delegations, said the official, who wasn't authorized to comment publicly on the matter and requested anonymity. The guards' release left the U.S. struggling to point to anything that amounts to accountability. It also fueled the perception that the U.S. allows Turkey's leader to bring strongman tactics with him when he visits the U.S. capital. Last year, Turkish security officials manhandled several journalists at a Washington think tank where Erdogan was set to speak. "There must be consequences," Rep. Steny Hoyer, the No. 2 Democrat in the House, said Thursday. The State Department called the latest incident "deeply disturbing," insisting that a "thorough investigation that will allow us to hold the responsible individuals accountable is of the upmost importance to us." The fracas erupted as Erdogan arrived at the ambassador's residence following a meeting with President Donald Trump. Videos show people pushing past police to confront a small group of protesters across the street.

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