Six shots were fired in a drive-by shooting on the U.S. Embassy in Turkey’s capital Monday — the latest sign of growing anti-American tension in a dispute over a jailed Evangelist pastor.

The Ankara governor’s office said in a statement that an unidentified shooter fired six bullets at an embassy security gate from a passing vehicle at about 5.30 a.m. local time, with three bullets striking a door and a window. The embassy is closed for a week for holidays, and no one was hurt in the shooting.

Anti-American sentiment has been on the rise in Turkey in recent weeks amid a bitter dispute between Washington and Ankara that has sent relations between the NATO allies plummeting to their worst level in decades.

The tug-of-war over Andrew Brunson, an evangelical pastor who has been detained on terror charges by Turkey for nearly two years, has seen both parties levy tit-for-tat tariffs on each other’s goods. The sanctions have worsened Turkey’s currency crisis, fueling a wave of anti-American sentiment across the country as President Recep Tayyip Erdogan accuses Washington of trying to “bring Turkey to its knees.”

According to a report Sunday, the Trump administration knocked back a bid from Turkey to release Brunson in return for the wiping of billions of potential fines on a state-owned Turkish bank, Halkbank.

The Wall Street Journal, citing a senior administration official, reported that the Trump administration had rejected Ankara’s offer to hand over Brunson in exchange for dropping an investigation into Halkbank, a state-owned Turkish bank facing huge fines for allegedly violating U.S. sanctions on Iran. In May, Mehmet Atilla, head of international banking at Halkbank, was sentenced in a Manhattan court for his role in an Iranian scheme to skirt sanctions and wash $1 billion in oil revenue through the U.S. financial system.

According to the Journal, the U.S. has taken a hard line in it negotiations with its NATO ally, insisting all other issues are off the table until the pastor is free. “A real NATO ally wouldn’t have arrested Brunson in the first place,” the official said.

Analysts say Turkey has been seeking to use Brunson as a bargaining chip in its negotiations with the U.S. on a number of issues, including the Halkbank penalties, and the sought-after extradition of Pennsylvania-based Turkish cleric Fethullah Gülen, who Ankara accuses of having masterminded a failed coup attempt in 2016. The U.S. has refused to give up Gülen.

Turkey’s ailing lira, which has lost about 40 percent of its value against the dollar so far this year, has weakened further as a result of U.S. tariffs on imports of Turkish metals, and more U.S. sanctions could be imposed as early as this week, according to the Journal.

U.S. Treasury Secretary Steven Mnuchin said Thursday that his office stood ready to impose new sanctions if Brunson wasn’t released, while President Donald Trump took to Twitter to engage in saber-rattling over Brunson’s fate: “We will pay nothing for the release of an innocent man, but we are cutting back on Turkey!” he tweeted.

Amid the crisis, Erdogan has called on Turks to shore up the currency by not trading in dollars and euros; in response, patriotic Turks have posted videos to social media of them smashing iPhones, chopping up dollar bills, and pouring Coke down the toilet in protest at the U.S. sanctions.

Turkey accuses Brunson, who leads a small Presbyterian congregation in Izmir and has lived in Turkey for 23 years, of links to both Gülen and the Kurdistan Workers’ Party, a banned militant group that has been locked in an insurgency against the Turkish state for decades. But the U.S. says Brunson, who denies the charges, is innocent, and that the charges against him are politically motivated.