7.7-magnitude quake strikes Mariana Islands

7.7-magnitude quake strikes Mariana Islands

By Susannah Cullinane and Dave Alsup, CNN

Updated 1129 GMT (1929 HKT) July 30, 2016

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No tsunami warnings are issued
The quake is felt in neighboring Guam

(CNN)A 7.7-magnitude earthquake struck the Mariana Islands in the Pacific Ocean early Saturday.
The quake occurred at a depth of 117 miles (212 km) some 19 miles south-southwest of the uninhabited island of Agrihan in the U.S. territory, the U.S. Geological Survey said.

No tsunami warning has been issued, according to the National Tsunami Warning Center.
Spokesman Paul Whitmore said a barely noticeable wave of about two inches was recorded in Saipan, the largest of the islands.
The Commonwealth of the Northern Mariana Islands lies about 5,800 miles south-southwest of California's Pacific shore.
The quake was felt in the neighboring territory of Guam, with Twitter user @JRaemier telling CNN it woke her up and @Katfayeee saying it was the biggest earthquake she'd experienced.

@whosurtwit It was strong enough to wake me up and shake my things but no damage was done. It was quite long too
— Raemier Javelosa (@JRaemier) July 29, 2016

Read: Everything you need to know about voting in Mariana Islands and Guam
The USGS reported five smaller earthquakes in the Mariana Islands area over the next 10 hours. The next biggest measured 4.9 and occurred 7 miles (11 km) south of Agrihan at a depth of 122 miles.

CNN's Jennifer Hauser contributed to this report.