Mexico has deployed some 7,000 soldiers to the area of the volcano, which is near Mexico City, in case an evacuation becomes necessary. More than 25 million people live within 60 miles of the peak.
The mountain, which is taller than Mount Everest measured from seafloor to summit, erupted Sunday. Its lava appears to be contained, but scientists say the volcano has a history of rapidly changing.
It's a pandemic predicament. With only 1 recorded case of COVID-19 in their island nation, Tongans are desperate for help after the volcanic eruption — but eager to keep the virus out.
Indonesia, an archipelago of 270 million people, sits along the Pacific "Ring of Fire," which leaves the country prone to earthquakes, tsunamis and eruptions.