I always thought the cassowary was the modern day velociraptor.
Cassowaries are very, very fast, but they don't generally hunt in groups, to the best of my knowledge. That makes sense, since the critters are as big as they are....it would clean any food out of an area in a hurry if there were more than a couple working that area.
They
are the world's most dangerous bird, will eat meat on occasion, and are the largest meat-eating Avians on the planet, tho still classed as omnivores ....but they are ratites, and cannot fly. When they are pursued as food, its is usually with dogs. There are other Ratites, such as the Rhea in South America, and the ostrich, but those are pretty much grazers on seeds and grasses
The velociraptor hunted in packs, apparently were able to communicate in simple ways, and used tricks such as driving prey to a hidden pack member...Harris' Hawk does many of these sorts of things, with the second advantage of high flight and great eyesight. They operate in concert with a hawker but will also work with a hunter's dogs who push targets out of the brush and into range of the hawks.