SYDNEY, Australia -- A seven-year-old boy broke into a popular Outback zoo, fed a string of animals to the resident crocodile and bashed several lizards to death with a rock, the zoo's director said Friday.

The 30-minute rampage, caught on the zoo's security camera, happened early Wednesday after the boy jumped a security fence at the Alice Springs Reptile Center in central Australia, said zoo director Rex Neindorf.

The child then went on a killing spree, bashing three lizards to death with a rock, including the zoo's beloved, 20-year-old goanna, which he then fed to "Terry," a four-metre long, 200-kilogram saltwater crocodile, said Neindorf.

The boy also fed several live animals to Terry by throwing them over the two fences surrounding the crocodile's enclosure, at one point climbing over the outer fence to get closer to the giant reptile.

In the footage, the boy's face remains largely blank, Neindorf said, adding: "It was like he was playing a game."

By the time he was done, 13 animals worth around US$5,500 had been killed, including a turtle, bearded dragons and thorny devil lizards, Neindorf said. Although none were considered rare, some are difficult to replace, he said.

"We're horrified that anyone can do this and saddened by the age of the child," Neindorf said.

Alice Springs police said they are unable to press charges against the boy because of his age. Children under age 10 can't be charged with criminal offences in the Northern Territory. His name was not released because of his age.

Neindorf said he plans to sue the boy's parents.

The boy's small size is probably the reason he didn't trip the zoo's security system, which relies on sensors to detect intruders, Neindorf said.

"I just want people to learn that they can't let their children go and run amok," Neindorf said. "If we can't put the blame onto the child, then someone has to accept the responsibility."