According to NBC New York, "A man is in critical condition after he was attacked by a tiger in the tiger den at Bronx Zoo, police sources say. The man lost his foot in the attack" and is now at Jacobi Hospital. It's unclear, as of this moment, how the man got into the tiger den and whether or not it was an accident, but the zoo is preparing a statement and we'll let you know what it says.
Update: An FDNY spokesman tells the Times, "It sounds like he had some severe deep cuts to his back and a severe injury to a leg." The man is in his twenties or thirties and either "fell or jumped from a monorail."
Update II: DNAinfo reports that the man jumped from the monorail in an apparent suicide attempt. "The man told those who rescued him that he jumped in on purpose because 'he wanted to die,' sources said."
Update III: The NYPD tells the AP that the man, who "climbed over two fences to reach the enclosure" (after jumping down from the monorail, we guess), has lost a leg.
Update IV: A statement from zoo director Jim Breheny:
A passenger on the Bronx Zoo’s Wild Asia Monorail jumped out of the car he was riding in, clearing the exhibit’s perimeter fence into a tiger exhibit around 3pm today. Our emergency response staff immediately went to the site and used a CO2 fire extinguisher to move the tiger away from the person. Once the tiger backed off, the man was instructed to roll under a hot wire to safety. The keepers were able to call the tiger into its off exhibit holding area and safely secured the animal. The man, about 25 years of age, conscious and talking, was taken to the hospital by ambulance. If not for the quick response by our staff and their ability to perform well in emergency situations, the outcome would have been very different. For information on the condition of the individual please contact the hospital.