The parents of a teenager mauled to death by a tiger in San Francisco Zoo on Christmas Day have spoken of their shock and anger.

Carlos and Marilza Sousa choked back tears as they spoke of their son Carlos Jr, who died after a rare Siberian tiger escaped from her cage and mauled three people. The 300lb (135 kg) animal was shot dead by police.

“I wish I was sleeping and this was just a bad dream, but it’s not,” Mrs Sousa told the Associated Press at her San Jose home.

Today the zoo was shut and the big cat enclosure remained cordoned off as a crime scene as detectives tried to work out whether carelessness or sabotage had helped the tiger to escape from its secure pen, which had been reinforced after the animal, named Tatiana, was involved in an earlier mauling incident last Christmas.

The enclosure is surrounded by an 18ft (5.5m) wall and a 20ft (6m) moat.

The Sousas said that they were angry that they had been left to learn of their son’s death from the coroner’s office, as neither police nor zoo officials had got in touch with them.

“They didn’t call, like we lost a dog or a cat. But we do have questions. How did this happen? This isn’t the first time, either,” said Mrs Sousa.

Only about 20 visitors remained at the zoo when the attacks happened, about an hour before the 6pm closing time, officials said.

Mr Sousa junior was the first person to be attacked when the tiger escaped, and was mauled directly outside the tiger’s enclosure. He died at the scene.

Alerted by frantic emergency calls, police armed with shotguns cordoned off the zoo and scoured the densely populated area around it with helicopters in case other tigers had escaped from their pen.

Tatiana was discovered by four officers with one of her bloodied, but still alive, victims about 300 yards away from her pen, in front of a cafe. The police chief said the animal was mauling the man, and when officers yelled at it to stop, it turned toward them and they opened fire.

Only then did they see the third victim, police said.

“When the officers first approached this other victim in front of the café, the tiger was sitting right next to the victim. As the officers approached, the tiger continued its attack,” Sergeant Steve Mannina, a police spokesman, said.

“As the officers moved even closer, the tiger focused its attention on the officers and started coming towards the officers. That is when the officers fired.”

The two injured men, 19- and 23-year-old brothers from San Jose, were said to be in stable condition at San Francisco General Hospital after surgery. They suffered deep bites and claw wounds on their heads, necks, arms and hands, but are expected to recover fully, according to Dr Rochelle Dicker, a surgeon.

The zoo has a response team that can shoot animals. But zoo officials and police described the initial moments after the escape as chaotic.

Siberian tigers are an endangered species, with fewer than 400 surviving in the remote forests of Russia’s Sikhote-Alin mountain range, east of the Amur River. Another 600 are kept in captivity.

Four-year-old Tatiana was moved to San Francisco Zoo from Denver in the hope that she would mate with a male called Tony. She lived with Tony and three Sumatran tigers in outdoor enclosures.

New safety features were added to the compound after Tatiana chewed flesh from a keeper’s arm three days before Christmas last year. Lori Komejan was mauled in front of horrified spectators during a public feeding session as she reached through a drain to retrieve an object from Tatiana’s cage.

Pinned to the cage bars, Ms Komejan escaped only when a colleague grabbed a mop and hit the tiger on the head until she let go.

A state investigation found that the tiger cages were configured in a way that made it possible for Tatiana to reach under the bars to bite the keeper. The zoo made improvements that cost $250,000 (£126,000), including adding steel mesh to the bars and increasing the distance between the big cats and the public, before resuming public feedings in September.

Zoo director Manuel Mollinedo said yesterday that he gave no thought to destroying Tatiana after the 2006 incident, because “the tiger was acting as a normal tiger does”. As for whether Tatiana showed any warning signs before Tuesday’s attack, Mollinedo said: “She seemed to be very well-adjusted into that exhibit.”

One zoo official insisted the tiger did not get out through an open door and must have climbed or leaped out.

But Jack Hanna, former director of the Columbus Zoo and a frequent guest on TV, said such a leap would be an unbelievable feat, and virtually impossible. “There’s something going on here. It just doesn’t feel right to me,” he said. “It just doesn’t add up to me.”

Instead, he speculated that visitors might have been fooling around and might have taunted the animal and perhaps even helped it get out by, say, putting a board in the moat.

Ron Magill, a spokesman at the Miami Metro Zoo, said it is unlikely a zoo tiger could make such a leap, even with a running start.

“Captive tigers aren’t nearly in the kind of shape that wild tigers have to be in to survive,” he said. He said taunting can definitely make an animal more aggressive, but “whether it makes it more likely to get out of an exhibit is purely speculative.”

Police Chief Heather Fong said the department has opened a criminal investigation to “determine if there was human involvement in the tiger getting out or if the tiger was able to get out on its own”.

The police chief would not comment on whether the animal was taunted.

Fatal attraction

— A man was killed by two Bengal tigers at a zoo in Assam, northeast India, this month. He had jumped a barricade and put his arm through the bars to take a photograph

— In February a girl aged 6 was killed by a tiger at the Kunming Zoo in Yunnan province, China, after being urged to pose beside it, unprotected, for a photograph

— Last year a drunk man was mauled by a panda at Beijing Zoo after attempting to hug it

— In 2003 a US soldier shot dead a Bengal tiger at Baghdad Zoo after it bit a fellow serviceman who had reached into its cage to feed it

— A lioness at Kiev Zoo, Ukraine, killed a man last year who climbed into the enclosure and shouted, ‘God will save me, if he exists’

Sources: www.bornfree.org.uk; www.peta.org ; Times archives

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