WASHINGTON (AP, RFE) — The U.S. Justice Department says it is “gravely disappointed” by Germany’s decision to deport Adem Yilmaz to Turkey instead of extraditing him to the United States as Washington had demanded.

Yilmaz was indicted in the United States in 2015 on charges he attacked U.S. military forces in territory along the border of Afghanistan and Pakistan and that he gave instructions to a man involved in a 2008 suicide bombing that killed U.S. soldiers.

Acting U.S. Attorney General Matt Whitaker, in unusually harsh language for a U.S. ally, on February 6 said the Germans this week had deported Yilmaz to Turkey despite a pending a U.S. extradition request.

The US Department of Justice says it is “gravely disappointed” by Germany’s decision to deport Adem Yilmaz to Turkey instead of extraditing him to the United States, as Washington had requested.

Yilmaz was charged in the United States in 2015 for attacking US military forces on territory along the Afghan-Pakistani border and instructing a man involved in a 2008 suicide bombing by US soldiers.

Acting US Attorney General Matt Whitaker, in language unusually harsh to a US ally, said on February 6 that the Germans had deported Yilmaz to Turkey this week, pending a US extradition request:

We are gravely disappointed by Germany’s decision to deport a dangerous terrorist — Adem Yilmaz — to Turkey, rather than to extradite him to the United States to face justice for his complicity in the murder of two American servicemen.

Whitaker said the U.S. government had sought review of a “German court’s recent decision to change the terms of our extradition treaty with Germany and deny his extradition to the United States.” Instead, he said, the “German government deliberately helped Yilmaz escape justice by placing him on a plane to Turkey.”

“The German government has refused to take any responsibility for failing to extradite him to the United States, has flouted their treaty obligations, and has undermined the rule of law”, Whitaker said.

A senior U.S. official told Bloomberg that the United States had filed a “red notice” through Interpol to have Yilmaz detained in Turkey.