I've had multiple issues with hawks trying to snatch guineas. A while ago, they were out near our work shed. Luckily my whole family was out there, and we had some friends over.
The hawk swooped down out of no where and grabbed a guinea. I watched in horror. Luckily guineas will fight and wriggle to the death if something even touches them.
The guinea forced the hawk to drop him and land in a tree. The guinea was fine, just had a small limp.
Everyone walked right into the coop, after we could get them in there.
I've actually seen this happen quite a lot out here.