Those are not the best-regarded wheels, so it is possible that they failed. A hub lockup is unlikely. In such a low spoke-count wheel, one broken spoke can cause the wheel to go so out-of-true that it may jam against the brake pad and cause an endo; one broken spoke could lead instantly to a couple more broken spokes or they could have been broken in the crash.

More likely is that you did pick up a stick or something that got caught in the wheel and caused a lockup. Look for marks on your fork and spokes that might indicate this kind of trauma.

As others have noted, though, It's also possible that you hit an obstruction and went over the front. That happened to me last week, I think - at least, the same thing happened, and I can't find any bike malfunction to explain it.