SAN FRANCISCO, California (CNN) -- Police are investigating whether several items found in the enclosure of a tiger who fatally mauled a 17-year-old man show that the animal was attacked or taunted, San Francisco Zoo spokesman Sam Singer said Wednesday.
Police are examining a large rock, a tree branch and other items, Singer said.
"They [police] are trying to make a determination that those items or any other things that happened on Christmas Day were part of some attack on the tiger or something that angered Tatiana, causing her to come out of her cage," the spokesman said.
San Francisco Police Chief Heather Fong has said that a shoe print found on the railing at the tiger enclosure is being examined to determine if one of the victims climbed over the rail or threw their leg over the side.
"Something prompted our tiger to leap over the exhibit and all I can do is ensure that's never going to happen again at the San Francisco Zoo," said the facility's director Manuel Mollinedo Wednesday.
"Corrections" are under way at the habitat as the zoo prepares to reopen Thursday, he said. A series of temporary security measures will be in place, with more permanent improvements to follow. Those will include raising the wall around the tiger habitat to 19 feet, adding security staff and installing a speaker system to alert visitors in the event of another emergency, Mollinedo said.
The zoo's large cats will be kept indoors until workers complete the improvements to their enclosure.
A memorial area will be on display Thursday near the entrance to the zoo and visitors are encouraged to bring mementoes and tributes -- both to the mauling victim and Tatiana.
Signs are also going up at the zoo advising people to be respectful of the animals.
Meanwhile, the two brothers who survived the attack said they were denied help for at least 30 minutes by zoo security who did not take their pleas seriously, an attorney representing Paul Dhaliwal and Kulbir Dhaliwal said Tuesday, according to The Associated Press.
The 300-pound Siberian tiger apparently jumped a 12½-foot wall December 25 and killed Carlos Sousa and injured his friends.
The wall was determined to be nearly 4 feet shorter than industry standards. The dry moat between the wall and the exhibit, built in 1940, measures 33 feet.
A source close to the investigation said the rock found in the habitat measured 9 inches, and a tree branch and pine cones were found that came from trees that were not near the tiger's enclosure.
Zoo employees did not see the items in the enclosure before the tiger escaped, the source said.
Singer said zoo employees also alerted police to an empty vodka bottle in the car in which the young men came to the zoo.
He called the brothers' statement that they were ignored "unreliable."
The brothers tried to get help for Sousa after attempts to stop the tiger failed, attorney Mark Geragos said. Watch what Geragos might do »
The animal first mauled Sousa and Paul Dhaliwal about 4:30 p.m., the attorney said, according to AP. While Sousa was seriously hurt, Paul Dhaliwal escaped, and he and his brother ran 300 yards to a zoo cafe where they had earlier eaten.
But the siblings were denied entry to the cafe because the zoo was closing, the AP reported. At that point the brothers lost sight of the tiger. The brothers then saw a female security guard who appeared "diffident" when she was informed of the escaped tiger, Geragos said, according to AP.
"Who knows what would have happened if the guard had acted earlier?" Geragos said. "But Carlos would have stood a better chance of not dying. And maybe the police would not have shot the tiger as well."
Investigators from the U.S. Department of Agriculture are at the zoo, the AP reported.
The USDA issued several letters of warning to the zoo in the 1990s, but the findings were described as minor. A 1999 letter talked about sanitation and food storage issues, AP said.
The zoo paid a $500 penalty for problems inspectors discovered with veterinary care in 1992 and a $1,425 penalty in 2000 for sanitation problems at one animal facility.
That was the most recent action taken against the zoo, according to USDA spokeswoman Jessica Milteer, AP said. E-mail to a friend
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