Six US occupation soldiers in Syria have suffered "traumatic brain injuries" during two attacks that targeted illegal US occupation bases in the country this past week, the US Department of Defense said Thursday, adding that the soldiers were diagnosed during routine screenings carried out in recent days.

The disclosure further raises the human toll among American forces from strikes and counter-strikes in Syria last week to a total of 12 US occupation troops wounded. The attacks also killed an American contractor and injured another.

"Four service members suffered traumatic brain injuries at the US base near the Syrian city of Hasaka during a drone attack on March 23," Pentagon spokesperson Patrick Ryder said. Two others suffered injuries at the mission support site Green Village during an attack on March 24.

"All personnel in the vicinity of a blast are screened for traumatic brain injury. So these additional injuries were identified during post-attack medical screenings," Ryder told a news briefing.

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According to the Pentagon, the US shelling killed eight personnel in Syria.

The US claims that Iran was behind the attacks on its occupation bases, adding that those killed were not believed to have been Iranian, though they were associated with the Islamic Revolution Guard Corps (IRGC).

The New York Times on Monday highlighted that the Biden administration was yet to respond to an attack that killed an American contractor and injured six other Americans in northeast Syria, which the US claimed was of "Iranian origin, President Biden’s response has so far been more restrained."

The newspaper drew parallels between the Biden administration's dealing with a contractor dying during an offensive in an occupied country and the Trump administration's dealing with the issue.

Two American F-15s retaliated Thursday by launching airstrikes on several sites, which prompted the armed groups in Syria to retaliate against the US occupation, launching a barrage of rockets, as well as drone attacks, on Friday, injuring another American.

NYT, citing US officials, reported that US warplanes were set to go for another round of bombings late Friday, but the White House held off.

On Friday, several rockets and drones targeted US occupation bases in the Conoco gas field and Al-Omar oil field east of Deir Ezzor, Eastern Syria.

A few hours earlier, the US military said it carried out "precision airstrikes" in eastern Syria in response to an alleged drone attack that killed one American and injured five US service personnel.

A Department of Defense statement claimed that the casualties fell "after a one-way unmanned aerial vehicle struck a maintenance facility on a Coalition base near Hasakah in northeast Syria."

On Saturday, Syria slammed the savage aggression carried out by the US occupation forces on several areas in the Deir Ezzor Governorate that resulted in the killing of a number of people, the wounding of others, and material damage.

It is noteworthy that the US has for long employed the alleged "ISIS threat" as a pretext to continue its illegal occupation of northeastern Syrian territories.

US occupation forces frequently loot oil from Syrian gas fields and transport them to other occupation bases in Iraq via illegal crossings.