BEIJING — Don’t feed the pandas. That’s the rule apparently broken by a man who was banned for life from one of China’s major panda centers after throwing unspecified “objects” into an enclosure on Monday.

A notice from the Chengdu Giant Panda Breeding Research Base did not identify the objects, but said that feeding pandas can cause harm and that the panda appeared to be in normal condition. He identified the visitor as a 53-year-old man surnamed Gao.

“In view of Gao’s uncivilized visit and his behavior that may cause harm to the giant pandas, he is prohibited from entering the panda base… for life,” the notice said.

The panda base has previously imposed lifetime bans on feeding pandas. A man who fed bamboo shoots to panda cubs in an activity area and a woman who gave them peanuts were banned for life last August.

Other visitors have been banned for one to five years for offenses such as throwing water at a panda or banging forcefully on a window pane, according to state media reports.

The black and white giant panda has become a national symbol of China, loaned to zoos around the world. President Xi Jinping, during a visit to the United States last year, called them “envoys of friendship between the Chinese and American people.”

The breeding base in Chengdu, the capital of Sichuan province, is a popular tourist destination. A total of 34 pandas were born last year at two bases in Sichuan, including Chengdu. Some made a special appearance recently as part of this month’s Lunar New Year festivities.

“The national treasury has strict dietary regulations,” the Base wrote in its notice. She asked the visitors to be civil and lead by example.

By Sam