A giant panda has given birth to twin cubs at Smithsonian's National Zoo in Washington DC.
The panda, Mei Xiang, a star attraction at the zoo, gave birth to a pair of cubs hours apart on Saturday, the National Zoo said.
She gave birth to her first cub on Saturday after her water broke about an hour beforehand. About four and one-half hours later a second cub arrived and appeared healthy.
Zoo officials said Mei Xiang picked up the cub soon after giving birth and is being "a great mother".
Staff confirmed they were taking a cautious but hands-off approach to allow the mother and cub time together. The gender of the cubs will be determined at a later date.
Mei Xiang was artificially inseminated at the zoo in April. She had previously given birth to two surviving cubs: Tai Shan in 2005 and Bao Bao in 2013.
Pandas have a very low reproductive rate, particularly in captivity. There are about 1,600 giant pandas known to be living in the wild and some 300 in captivity, mostly in China.