US military officials have expressed concern about the increased risk of confrontation between US and Russian forces in Syria.
The commander of US Central Command (Centcom), General Erik Kurilla, said in a statement that his regional forces seek to avoid any miscalculated steps that would lead to unnecessary conflict.
"We seek to avoid miscalculation or a set of actions that could lead to unnecessary conflict: that remains our goal," Kurilla said in a statement.
He described Russia's recent actions as "provocative and escalatory," referring to the recent raid on al-Tanf.
The Wall Street Journal quoted Pentagon officials as saying there were fears of a clash with the Russians, accusing the Russian forces of "significant increase in the provocation" this month.
A US military official said that Russia launched a raid on sites in al-Tanf region last Wednesday, near the US base, which manages a mission to train and advise local fighters to combat the resurgence of ISIS.
After Russia informed the US through a communications line that it was carrying out the operation in response to a supposed attack against Syrian government forces, its military aircraft struck "a combat outpost at the garrison," a US military official said.
The official explained that two Russian Su-35 and Su-24 aircraft hit a military site, and although the raid did not target US forces, officials expressed concern that the attack constituted a challenge to the mission of US forces in Syria.
The newspaper reported that Russia sent two Su-34 warplanes to the area where the US forces conducted a raid in northeastern Syria to "apprehend an ISIS bomb maker." However, it quickly withdrew them after US F-16 fighters headed to the area.
US officials also discussed other incidents in the past two weeks without revealing their details.
About 200 US soldiers are stationed at al-Tanf base, out of the 900 soldiers deployed in northeastern Syria.
Russia withdrew several of its forces and military equipment from Syria after it invaded Ukraine, and experts warn of the "vacuum" that Iran could exploit to replace it.
Russia has escalated its interventions in locations close to the deployment of US forces to ensure that it can still carry out military operations in more than one place at the same time.
In 2016, Russian warplanes bombed al-Tanf base after two US Navy F-18 planes on patrol in the area left to refuel. The base was empty of US forces at the time and several Syrian fighters were killed, whom Russia described as terrorists.
In 2017, Russia issued a 48-hour ultimatum for the US to withdraw its personnel from the base, but Washington refused, and nothing happened.
However, the most dangerous incident between the Russian and the US forces was in 2018, after fighters of the Russian "Wagner" group advanced to eastern Syria and fired at the US forces.
They ignored the warnings of the US army, which asked them to leave. US troops then launched an attack against Russian forces, killing "a few hundred," according to former US Secretary of State Mike Pompeo.
The Russian military announced that it had nothing to do with the incident.