WASHINGTON (AP) -- The Smithsonian's National Zoo says giant panda Mei Xiang (may-SHONG) is in labor.
The zoo tweeted Friday afternoon that the panda's water broke and she is having contractions. Zoo spokeswoman Pamela Baker-Masson said in an email that "everyone is just watching" on the panda cams.
The zoo has been on 24-hours-a-day panda watch since Aug. 7.
A Chinese panda expert performed artificial inseminations on Mei Xiang on March 30 after she failed to breed naturally with male panda Tian Tian (tee-YEN tee-YEN).
Mei Xiang has given birth to two cubs. Tai Shan was born in 2005 and a week-old cub died last September.
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