Twin Pandas Born at Japanese Zoo

— -- The world’s panda population increased by two this week as 14-year-old giant panda bear named Rauhin gave birth to twin female cubs at the Adventure World zoo in Wakayama Prefecture, Japan.

The two sister cubs, yet unnamed, were born three hours apart on Tuesday evening.

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The first cub to be born tipped the scale at 6.38 ounces and measured 8.66 inches long. Her sister weighed in at a slightly heavier 6.56 ounces and measured 8.26 inches.

Zookeepers said the birth went off without a hitch and that the two cubs were healthy. When fully grown, giant pandas can weigh as much as 125 kilograms (276 pounds).

This was the fourth delivery for Rauhin. She's now the mother of seven.

Rauhin’s partner Eimei is 22 years old and has sired 13 babies so far.

Adventure World has not yet decided when the mother and nursing cubs will be on display for visitors.