In the opening credits, we see a knife being pulled out of a man's bloody gut. (See paragraph 6 for more details)
Jack, while trying to control the elevator's procedures, is stabbed in the eye with elevator equipment. We see the equipment go in the eye and then cutting away to Ethan and Sarah but gory sound effects are heard after. This is the most graphic and intense scene in the movie, and it might disturb/disgust some viewers. But because of the elevator going up all the way to a detailed floor, we can imply that after he is impaled through the eye, he is crushed. However, we only know that he is dead, hence why the film probably got a PG-13 rating for intense violence.
Claire gets into her car, and then the car explodes. No possible explanation of what happens after that, but we hear that she dies.
Jim apparently during the mission is shot, and on IMF camera equipment, we see his hands full of blood, and falls off of the bridge, and into the water. We later learn that he faked his death.
Ethan throws an explosive disguised as gum onto a fish tank; It shatters and the whole building is flooded, with him jumping out just in time. No reported casualties.
(Continued from paragraph 1) The target of Ethan's mission is seen being stabbed to death, you see some blood on the gate. Later, we see one of Ethan's recruits is actually the one who killed him, with the stabbing clearly seen. Ethan searches the man, we see blood on his clothes. Sarah is also found dead, we see no blood on her, but we see the knife used held up by Ethan, with blood on it and possibly little bits of gore.
Ethan contacts the IMF, with blood still on his hands, at a public telephone. He wipes off the blood with a napkin.
A man holds out his bloody hands at another man, walking slowly towards him.
Ethan grabs Claire and searches her.
A man shoots a woman and she dies. He then hits another man in the head and he is dazed.
A helicopter is blown up and crashes in a tunnel; A man that was holding on to the helicopter is smashed against the train tracks (this is only briefly seen).