The world's first gorilla born in a zoo has died aged 60, the Columbus Zoo and Aquarium said.

Colo became known as the oldest known living gorilla in the US and died in her sleep, less than a month after her birthday.

She surpassed the average life expectancy of captive gorillas by two decades.

Columbus Zoo President and CEO Tom Stalk said: "Today is a sad day for us.

"We look at her role and how important she was, a matriarch for not only our gorilla family but for our entire Columbus Zoo family.

"She's an icon for Columbus, Ohio and the Columbus Zoo. She's a fantastic ambassador and when we talk about 60 years, the first gorilla ever born in human care and the oldest gorilla in the world by more than two decades."

Colo was born at the Ohio zoo on December 22, 1956.

She became a mother of three, grandmother of 16, great-grandmother of 12 and great-great-grandmother of three.

In December, hundreds of people gathered at the zoo on her birthday where the zoo decorated her enclosure with multicoloured paper chains and cakes of squash and cornbread with mashed potato parsley.

The zoo said the gorilla's body will be cremated and buried at an unspecified location at the zoo.