(CBS News) LONDON -- In the Syrian civil war, the Assad regime stands accused of war crimes for attacking civilians. Now rebels trying to overthrow Assad are .
On Friday, the independent group Human Rights Watch said that in August, rebels attacked civilians in the province of Latakia, killing at least 190. Witnesses say the attackers went door to door, killing entire families in some cases.
The report cites five rebel groups as the main perpetrators of this attack, which it describes as the first documented case of rebel forces deliberating targeting civilians. It highlights the role of one relatively new, but increasingly important, group called the Islamic State of Iraq in Syria, known as ISIS. It is strongly allied with al Qaeda and it's largely composed of foreigners. But it also has a lot of influence on the ground.
It is also important to note that there were moderate groups involved in the attack, as well, including some of those backed by the U.S.
As for the moderate rebel groups backed by the U.S., the attack leaves them in a precarious position. It's so difficult to know which group to support, when the moderate groups that the U.S. has been backing have, at best, failed to stop this from happening, and at worst, participated in it.