SAN FRANCISCO -- Just months after a tiger escaped from its exhibit and went on a deadly Chirstmas Day rampage, San Francisco Zoo officials have announced the birth of a tiger cub at their facility -- the first time a Sumatran Tiger has been born at the Zoo since 1956.

Officials said staff members noticed the mother, Leanne, was beginning to show birthing activity Thursday and confirmed at least one cub was born by Friday morning.

It was the first time since 1956 that a Sumatran tiger, an endangered species, has been born at the zoo, officials said.

The cub will not be exhibited for several months while it gains strength and coordination and bonds with its mother.

Leanne was born at the Toronto Zoo and is on a breeding loan from the San Antonio Zoo. The father, George, was born at the Henry Doorly Zoo in Omaha and is on loan from the Downtown Aquarium in Denver.

"Being a first-time mom, we are very pleased with Leanne's behavior," said Jacqueline Jencek, the zoo's chief of veterinary services. "This is a very critical period for both mom and cub, but from our initial observations Leanne is very attentive and gentle."

On Christmas Day, Tatiana, a 350-pound Siberian tiger, escaped her exhibit and fatally mauled a 17-year-old from San Jose. Police were forced to shoot and kill Tatiana.

Since that time the wall surrounding the Big Cat exhibit has been increased by several feet and an internal investigation into the incident is still ongoing.