There is pervasive violence, blood and gore throughout the movie.
Lots of blood spraying.
A man hits a zombie with a croquet mallet, breaking it. Then, as the zombie attacks him he impales the head of the zombie with the broken piece of wood. Blood is seen coming out of the bottom of his head and as the spike exits the top of the zombie's head, we see brain matter and blood squirt out.
A man has his neck bitten by a zombie. We see veins and entrails get ripped out, and see the inside of his neck. During this scene there is a lot of blood spraying out of the man's neck.
Many zombies are shot in the head, usually no blood. In one scene in particular, a zombie's head is blown apart, sending pieces of it flying around the room. The walls are covered in fleshy chunks and brain matter as well as large amounts of blood and gore after this scene.
A man trips and accidentally kills a woman with a chainsaw. We see the saw slice her in half from the shoulder down to her waist. The saw rips her shirt apart as it rips her flesh apart sending blood and gore spraying around the area. For a quick moment we also see her insides start coming out and hit the chainsaw, making for a gory mess.
A man is hit by a speeding ambulance. We see his body literally break in half as the ambulance collides with him sending him flying into a yard.
A speeding car crashes into a gas station, resulting in a large and violent explosion.
A man gets surrounded by a horde of zombies, and as he is about to get eaten, he blows up a tank of propane gas, killing many zombies as well as himself.
A legless zombie is shot point blank range in the head with a shotgun. The impact is not seen, but we see the remains of his head splatter against a wall behind him.
We see many reanimated corpses walking around in various stages of decay, with opaque eyes (or the lack thereof), darkened veins, limp rotten skin, exposed innards/bones, and usually with many gruesome injuries inflicted on their bodies prior to death that have since coagulated and rotted out.
The reanimated corpse of a large woman charges at a group of survivors. One of the survivors grabs a fireplace poker and stabs it into the eye of the zombie and pushes it in deeper until it breaks out of the back of the zombie's head, killing it.
The group of survivors turns kerosene tanks into homemade bombs to deal with the hordes of zombies. We do not see an initial impact from the explosion but see burning bloody limbs lying everywhere afterwards and see zombies walking with severe injuries from explosions (missing body parts, on fire, mutilated, etc...)
Many zombies got sliced with a chainsaw through the side of a bus. We see legs and arms get sawed off, a few zombie's torsos get sawed open, and we see one unlucky zombie's head get sawed in half, causing what's left of its brain to ooze out.