NEW YORK (CNN) -- Seven people, including three children, died Sunday when a vehicle flipped over a guardrail and plunged up to 60 feet to the ground, landing upside down in an area of the Bronx Zoo that is closed to the public, officials said.
All the victims were inside the vehicle, a New York police spokesman said. The crash occurred near the Bronx River Parkway and East 180th Street.
"The vehicle hit the median and went across all lanes of traffic in the opposite direction," the spokesman said. The drop from the ramp, he said, was "substantial."
The victims include an 84-year-old man; three women, ages 80, 45 and 30; two girls, ages 12 and 10; and a smaller girl whose age was unclear, the New York Fire Department said. A baby bag with diapers inside was found at the scene.
The vehicle was traveling at a high rate of speed, said FDNY Deputy Chief Ronald Werner.
An eyewitness told authorities it wasn't apparent what caused the vehicle, a white Honda Pilot SUV, to strike the barrier and plunge off the road, according to a law enforcement official. The van flew about 55 to 60 feet through the air before plunging the same distance to the ground, the official said.
One of the women was driving the SUV, the official said, but did not know which one. The victims' names were not released pending notification of family members.
Zoo spokeswoman Mary Dixon said the vehicle landed just inside the southeast perimeter of the 265-acre zoo.
"It's far from any public area," Dixon said. "No animals, exhibits or visitors were affected. ... It would be impossible for any visitors to see this."
The area where the vehicle fell is adjacent to where the zoo's trams are parked, Werner said.
The fire department's Howard Sickles told reporters that in his 20 years he's "seen a lot of horrific things and this is one of them."
The crushed vehicle came to rest in overgrown brush, Werner said. Authorities used thermal imaging cameras to find victims in case any had been ejected, he said.
Authorities received multiple calls about the incident at about 12:30 p.m., Werner said.
The vehicle was heading southbound on the Bronx River Parkway at the time of the incident, according to the NYPD.
Authorities said it was unclear whether any of the victims were wearing seat belts.
In 2006, six people died in an accident on the Bronx River Parkway near the site of Sunday's crash.
CNN's Miguel Susana, Steve Kastenbaum, Ross Levitt and Susan Candiotti contributed to this report.
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