A white tiger at the Qingdao Zoo in Shandong province has died after fighting with another white tiger, according to a statement released by the Qingdao Municipal Park Center on Thursday.

The incident occurred on Sunday morning when the two white tigers were released into the same outdoor enclosure and subsequently began to fight, resulting in one of the animals suffering fatal injuries.

A preliminary investigation found that a zookeeper had violated operating procedures by releasing the tigers into the same space.

In the statement, the center acknowledged shortcomings in the implementation of management procedures and daily supervision, and issued an apology to the public and those who care about the zoo.

According to Nanjing-based Modern Express newspaper, the tiger that died was a well-known attraction at the Qingdao Zoo and had become an internet sensation in recent years because of its distinctive appearance. The tiger was given the name "Xiao Nao" because it was shy and somewhat timid when it was young.

Relevant authorities have intervened and launched an investigation. Those found responsible will be held accountable in accordance with regulations, the statement said.

The Qingdao center also pledged to improve its management system, strengthen supervision, strictly enforce operating procedures, and take measures to prevent similar incidents from occurring in the future.

Hu Qing contributed to this story.