According to debka, the terrorists infiltrated the camp, captured weapons and ammunition, and engaged in firefights with US forces. Probably impossible to know how many casualties until it’s over.
More details are available on the hebrew version of debka (need to translate this article into English):
www.debka.co.il/article/22354
Not sure why by debka gives a lot more details of things on the hebrew side of their website than the english side.