Residents scamper to safety after a 6.8 earthquake hit near Cebu City on Monday.

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The official death toll is 48, with 92 people missing

At least nine earthquakes above magnitude 4.6 have rattled the region since Monday

The 6.7-magnitude earthquake struck just before noon Monday

CNN  — 

A 6.8-magnitude earthquake struck Monday off the third-largest island in the Philippines, prompting the country to issue a tsunami alert for the coastlines near the epicenter.

Another 92 people were reported missing as the nation’s military scrambled 1,000 government troops to deal with the disaster, according to the Philippines News Agency.

“We have dispatched two … choppers from Western Mindanao Command to help in the relief operations,” military spokesman Col. Arnulfo Burgos Jr. said.

The 6.7-magnitude earthquake struck Monday off Negros, the third-largest island in the Philippines. The earthquake occurred in the ocean at a depth of 20 kilometers (12 miles), according to the U.S. Geological Survey.

At least eight aftershocks, ranging from magnitude 4.6 to 6.0, had rattled the area into Tuesday, the USGS reported.

The Philippines is situated in the so-called Ring of Fire, an arc of fault lines circling the Pacific Basin that is prone to frequent earthquakes and volcanic eruptions.

CNN’s John Dear contributed to this report