A staff member of Chongqing Zoo takes care of two pairs of newborn giant panda twins at an outdoor naming ceremony in southwest China's Chongqing Municipality on September 30 (XINHUA)

Four newborn giant panda cubs made their first public appearance on September 30 at the Chongqing Zoo in southwest China.

The cubs, two pairs of twins, were all born on June 23, a rare case in the breeding history of captive pandas in the world.

Their names are Shuangshuang, Chongchong and Xixi, Qingqing, combining to symbolize "double joy and happiness" in Chinese.

The four cubs have been growing well, with Shuangshuang being the heaviest at 5.8 kg and Xixi the lightest at 4 kg, said Yin Yanqiang, the giant panda technical supervisor with the Chongqing Zoo.

Starting on September 30, tourists can watch the cubs outside the window of the cub nursery from 10:30 a.m. to 11:30 a.m. and from 1:30 p.m. to 2:30 p.m. every day, according to the zoo.