The app was down on various operating systems in parts of India, Canada, the U.S. and Brazil, Reuters noted.
Facebook shares are down 2.4% after hours.
Updated 8:04 p.m.: "We have now fixed the issue and apologize for the inconvenience," WhatsApp says of an outage that lasted "a few hours."
Previously: Facebook beats with Q1 report, nears 2B monthly users (May. 03 2017)
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