MEXICO CITY, April 19 (UPI) -- Mexico's Popocatépetl volcano erupted on Monday, launching ash and burning rocks into the air and showering the city of Puebla with hot ashes.
At least five eruptions were reported.
The historic city of Puebla, which lies 25 miles east of Popocatépetl in central Mexico, was covered in ash, forcing the airport to close.
Volcanic activity has increased in the past month at Popocatépetl, about 43 miles southeast of Mexico City. But activity had decreased for nearly a week before Monday's eruptions. There were eight eruptions recorded in Popocatépetl in the week prior to Monday, but there were 31 eruptions in the six days prior to that week.
The environmental alert level was raised in March to the second degree out of three, meaning nearby residents should be prepared to evacuate.
The alert level was not raised after Monday's eruption, which saw no accompanying tremors.
Officials have warned nearby residents to avoid the area, adding that low-level to intermediate-level explosive activity is expected.
