The U.S. has around 900 soldiers in Syria, mostly split between the At-Tanf base in the south and the country’s eastern oil fields.

They work with the Syrian Democratic Forces (SDF), a disproportionately Kurdish militia, to combat the remnants of ISIS.

However, the Syrian government, led by President Bashar al-Assad, has long considered their presence illegal and demanded they leave.

The Syrian Foreign Ministry reiterated this position in a statement on Monday that read: “The American side must immediately and unconditionally withdraw its military forces that are present on the territory of Syria illegally, refrain from stealing and smuggling Syrian oil and wheat, and lift the cover and protection from armed separatist groups and armed terrorist groups that are present.”

No evidence was provided to support the claim U.S. forces have been “stealing” Syrian wheat and oil, while the reference to “armed terrorist groups” is likely an attack on the SDF.

On Monday, a number of rockets hit the vicinity of the American Green Village base in eastern Syria, near the Iraqi border.

In a statement, U.S. Major General John Brennan, who leads the American-led coalition against ISIS, said the attack had not caused any injuries or damage, CNN reported.

A number of rockets failed to explode and were later cleared by American and SDF troops.

In a separate incident on Monday, drones were used to attack the At-Tanf base but again didn’t result in any casualties.

Just one of the drones managed to get into a part of the compound, which houses U.S. troops, before exploding, per CNN.

It is unclear who is behind the attacks, but previous incidents have been blamed by the U.S. on pro-Iranian militant groups.

The Syrian Foreign Ministry statement also addressed the case of Austin Tice, an American journalist who was kidnapped in Syria in August 2012.

U.S. authorities believe Tice is being held by the Syrian regime, with U.S. President Joe Biden giving a statement requesting his release earlier this month.

“On the tenth anniversary of his abduction, I am calling on Syria to end this and help us bring him home,” he said on August 10.

However, the Syrian Foreign Ministry said it “denies that it has kidnapped or disappeared any American citizen who entered its territory or resided in areas under the sovereignty and authority of the Syrian government.”

It accused Biden and Secretary of State Anthony Blinken of making “misleading and illogical statements” about the case.

In June, the Pentagon announced it is investigating a U.S. service member over an April 7 explosion at an American base in Syria, which left four wounded.

More than 350,000 civilians have been killed in Syria since the civil war began in 2011, according to the United Nations, with the Assad regime and its Russian allies accused of widespread torture and indiscriminate bombing.

The U.S. Department of State has been contacted for comment.