March 28 (UPI) -- Mexico's National Disaster Prevention Center raised its alert for the Popocatepetl volcano due to increased activity on Thursday.
The agency raised the warning level from yellow Phase 2 to yellow Phase 3 after an eruption occurred at 6:50 a.m. sending a plume of ash more than a mile and a half into the air.
It also recorded 61 exhalations at the volcano within the past 24 hours.
"The CENAPRED urges NOT TO APPROACH the volcano and especially the crater, because of the danger involved in the fall of ballistic fragments," the agency said.
Yellow Phase 3 is the highest level of warning before the red phase, which would include an advisory for people around the volcano to evacuate.
The Popocatepetl volcano is located in the states of Morelos and Puebla in central Mexico. At more than 17,800 feet, it's the second-highest peak in Mexico after the Citlaltepetl volcano.
Another eruption earlier this month sent ash nearly a mile into the air and spreading incandescent material within a 1.6-mile radius.