Bees generally only eat liquid and tiny grains like pollen- that’s what their mouthparts are adapted for, so it probably would have been some kind of wasp that you saw.
On the wider topic; traditionally one of the divisions between wasps* and bees was considered to be that bees are strict herbivores, while wasps are not. Like many of the traditional rules in biology though, it’s probably better as a guideline- as well as the carrion/vulture bees previously mentioned, there’s also a lot of species of ‘sweat bees’ which are drawn to drinking sweat for the tasty salty minerals, however that fits in the classification system. Even honey bees have been seen feeding on stuff like urine and faeces- again probably for the minerals, and quite possibly to feed to the larvae- so although I’m not aware of any records other than that crappy biblical ‘riddle’ (honestly, it’s worse than ‘what have I got in my pocketses’) saying honeybees eat meat, and they certainly don’t do it on a regular basis, slurping up the odd bit of blood or liquifying meat may well not be too much of a stretch if they got the opportunity. It’s not as though bees have a concept of yuck.
Best not to think about too much probably. Honey, anyone?
* For a given value of wasp- there’s a whole bunch of stuff called wasps as well as the ones people usually think of. Wood wasps, in the broader hymenopteran group, pretty much just eat wood. Probably.