CHENGDU, June 15 (Xinhua) -- Aili, a female giant panda living in southwest China's Chengdu Research Base of Giant Panda Breeding, gave birth to a pair of male twins Friday.

They are the third twins to be born on the base this year, weighing 163.8 grams and 136.5 grams respectively.

The mother panda's water broke at 9:53 a.m., delivered the first cub at 10:19 a.m. and the other at 11:07 a.m.

"This was Aili's first delivery, but she held and licked her cubs soon after, which showed her strong sense of maternity," said the base.