ISTANBUL (AP) — Shots were fired from a moving car at the U.S. Embassy in Turkey before dawn on Monday, an attack that came during heightened tensions between the two NATO allies.

There were no casualties and no claim of responsibility for the fleeting attack, in which three of the six bullets that were fired hit the embassy gate and a reinforced window.

“We can confirm a security incident took place at the U.S. Embassy early this morning. We have no reports of any injuries and we are investigating the details” embassy spokesman David Gainer said. He thanked Turkish police for their “rapid response.”

Turkey’s interior minister said police and intelligence units were searching for the car and suspects, stressing their motive would be established only after they are apprehended.

Suleyman Soylu speculated, however: “Is it a provocation following recent events or is it a common crime or is it an attempt to provoke by dressing it up as a petty crime?”

Turkish officials, who are locked in a trade and diplomatic dispute with the United States, condemned the shooting in Ankara.

Presidential spokesman Ibrahim Kalin tweeted that it was “an attempt to create chaos.”

A top official in Turkey’s ruling Justice and Development Party said the attack was a “clear provocation” and that foreign diplomatic missions are guests of the country.

“The utmost sensitivity will be shown to ensure their security,” said the party spokesman, Omer Celik. “Turkey is a safe country.”

The U.S. Embassy was scheduled to close at midday Monday until the end of the week for the Islamic holiday of Eid al-Adha, according to its website.

Tensions between the U.S. and Turkey are high, partly because of the case of Andrew Brunson, an American pastor who is being prosecuted in Turkey for alleged espionage and terrorism-related offenses that he denies.

U.S. President Donald Trump has called for his immediate release.

Turkey has long criticized the United States for not agreeing to hand over Fethullah Gulen, a Muslim cleric accused by Turkish authorities of engineering an attempted coup in 2016. Gulen denies those allegations, and Washington has urged Turkey to present convincing evidence for any extradition proceeding to go forward.

The United States recently imposed economic penalties on Turkey, including tariffs on Turkish steel and aluminum, that contributed to a slide in the value of the Turkish lira. Turkey’s economy is already vulnerable because of heavy foreign currency borrowing that fueled high growth for years.

Turkish President Recep Tayyip Erdogan, whose government imposed its own tit-for-tat tariffs on some American goods, alluded to the dispute with the U.S. in a pre-recorded holiday message.

“There is no difference between the direct attacks on our call to prayer and our flag and the attack on our economy,” said Erdogan, a pious Muslim who has drawn on religious and nationalist references in comments about the standoff.

He said defiantly, “Those who think they can make Turkey give in with the foreign exchange rate . will soon see they are wrong.” The lira has lost 38 percent of its value against the U.S. dollar since the beginning of the year.

U.S. diplomatic offices have been targeted in the past in Turkey, where various armed groups are active.

At least one suspect was wounded in a shooting outside the U.S. consulate in Istanbul in 2015. In 2013, a suicide bomber killed a Turkish guard and himself after detonating an explosive device outside the embassy in Ankara. In 2008, three assailants and three Turkish police officers died in a shootout outside the Istanbul post.

A security guard stands outside the entrance to the U.S. Embassy in Ankara, Turkey, Monday, Aug. 20, 2018. Shots were fired at a security booth outside the embassy in Turkey’s capital early Monday, but U.S. officials said no one was hurt. Ties between Ankara and Washington have been strained over the case of an imprisoned American pastor, leading the U.S. to impose sanctions, and increased tariffs that sent the Turkish lira tumbling last week. (AP Photo/Burhan Ozbilici)