A US plane lands on the flight deck of the USS Theodore Roosevelt aircraft carrier deployed to strike purported Daesh targets in Syria and Iraq. (Photo by Reuters)
A senior adviser to Syria's President Bashar al-Assad has accused US-led coalition forces of carrying out "intentional" airstrikes against a Syrian military airbase in Dayr al-Zawr province, where 62 soldiers were killed.
Buthaina Shaaban said in an interview with AFP on Sunday, "None of the facts on the ground show that what happened was a mistake or a coincidence."
The Syrian official also blamed Washington and its allies for colluding with the Takfiri Daesh terrorist group in the region.
"Everything was calculated and Daesh knew about it.... Even Russia reached the terrifying conclusion that the United States is colluding with Daesh," Shaaban stated, adding, "When Daesh advanced, the raids stopped."
The coalition aircraft, purportedly fighting Daesh in Syria, bombed the airbase on Saturday. At least a hundred soldiers were also injured.
Two F-16 and two A-10 jets entered the Syrian airspace from Iraq to conduct the attacks.
The US military says it halted the raids after Russian officials said the targets were Syrian government forces and not Daesh terrorists.
Elsewhere in her remarks, Shaaban said since the US-led intervention began in Syria in 2014, adding, "We have been saying that this is not against Daesh, that they are not striking Daesh."
The so-called coalition has been conducting the airstrikes in Syria without any authorization from Damascus or a UN mandate.
Many have criticized the ineffectiveness of the raids.
Washington and some of its regional allies have supported Takfiri groups fighting against Syria’s government.
The Syrian Foreign Ministry has called on the UN Security Council to condemn the attacks and to make the US respect Syria’s sovereignty.
Buthaina Shaaban, a senior adviser to Syrian President Bashar al-Assad
US airstrikes jeopardize ceasefire
Shaaban said such attacks could endanger a US-Russia brokered ceasefire deal meant to end hostilities in the conflict-ridden Arab country. 
She added that Damascus believed the Saturday raids may signal divisions within the US administration on deepening cooperation between Washington and Moscow under the truce deal.
"What is worrying is its effect on the US-Russia agreement. I believe that some elements in the United States do not want this deal," Shaaban said, adding, "There is a side that agrees with the Russians and another side that rejects the agreement. This makes it seem to us that the White House wants this agreement while the Pentagon rejects it."
However, Shaaban said Damascus was committed to the existing truce, adding, "We are committed to the truce. The truce is continuing until its expiration. Maybe it will be extended, maybe there will be another agreement."
On September 9, Russia and the United States agreed on a milestone deal on the crisis in Syria after marathon talks in the Swiss city of Geneva.
The deal, which went into effect on September 12 and was initially agreed to last seven days, calls for increased humanitarian aid for those trapped inside the embattled northwestern city of Aleppo.
Under the terms of the ceasefire agreement, Russian and US fighter jets would launch joint airstrikes against Daesh.