Panda cub born a week ago at the National Zoo dies

WASHINGTON (CNN) – A giant panda cub born a week ago at the Smithsonian’s National Zoo in Washington has died, the zoo said Sunday.

There were no outward signs of trauma or infection and it was not immediately clear what caused the cub’s death, the zoo said.

Veterinarians examined the cub Sunday morning after zookeepers and volunteers heard a “distress vocalization” from the cub’s mother, 14-year-old giant panda Mei Xiang. The cub did not respond to CPR and other life-saving measures, the zoo said.