The earlier reports weren't clear that all US forces involved came in on helicopter, but attacked from the ground.
The Syrians are saying all casualties were civilians and that they were in a civilian building under construction.
A report in The Guardian "US forces kill eight in helicopter raid on Syria" claims that reports of the aggression have spread across the Middle East already, insuring a major reaction (just hope it doesn't happen in your backyard). Syria says the four US military helicopter full of troops targeted a building under construction and witnesses said those who were killed were "building workers".
The mayor of al Qaim (al Da'im), Iraq said that the building attacked was surrounded by Syrian forces. (And somehow they managed to stay out of harms way pretty well, I guess.)
But the American source cited in earlier reports is quoted in the Guardian article saying the place was part of a "foreign fighter logistics network".
You can see Abu Kamal described as the sight of the attack and it's relationship to Baghdad, Mosul, and Tal Afar, Ar Ramadi, Hit, and other fun places. The river crossing the border near Abu Kamal is called the Eufrat when one zooms in an is most likely what we call the Euphrates. Even after zooming in the Google map did not show a Qaim or al Qaim, but did show an al Da'im east of Husaiba. Zooming in more and using the satelite view one can even make out the supposed WMD plant near "Qaim" that the ISIS site (linked in our previous report about this issue) was burning up about in 2002. That seems to indicate a difference of opinion in the spelling of a town's name who's pronunciation may fall in between al Qaim and al Da'im.
Zooming in on Abu Kamal it becomes apparent that there are too many buildings and too many of what appear to be farms to get any more information from the map, unlike the alleged nuclear plant al Kibar which was all alone. Interestingly, al Kibar is also on the Euphrates, along with, as we learned, al Qaim (al Da'im), Iraq where a yellow cake plant was suspected in 2002. But, since the Bush administration is so good at making booga booga stories out of thin air, I doubt they would have passed something like connection between al Kibar and al Qaim (al Da'im) if they could make something of this connection. Also, obviously, there was no yellow cake plant in Iraq at all in 2002 or the news would have been trumpeted around the world that we had found evidence of renewed nuclear activity in Iraq in order to justify the invasion.

On the picture to the right you can guess where Abu Kamal lies at the intersection of the white border line and the Euphrates. Al Qaim (al Da'im) is just 8 miles the other side of the border. Al Kibar is located under the double white squares monogramed with a "W" for Wikipedia just upstream (river flows towards Iraq) from the words "Dayr Az" (for a city, Dayr Az Zawr, apparently). It looks to be about 100 miles from the Abu Kamal-al Da'im area as the crow flies on a river that meanders down a crow's line of about 225 miles in Syria.