Mexico's huge Popocatepetl volcano erupted with an explosion of gas and ash that could be seen from miles, and could possibly create an ash cloud bound for Mexico City some 40 miles to the southeast.
Observers on the scene recorded video of the massive grey ash plume erupting from the volcano, which has been restive since last year.
The ash plume stretched four kilometers into the sky and dropped incandescent chunks of rock into neighboring areas, according to Mexican newspaper Informador.
A volcanic alert has been issued for the area.
More from GlobalPost: Mexico readies evacuation plan as Popocatepetl rumbles
If eruptions continue, it's possible that evacuations may be ordered for residents of the villages near the volcano. Evacuations were planned as the volcano's activity grew ominous in mid-May, but were never carried out.
Another large eruption of ash was recorded on May 22, accompanied by two small earthquakes, indicating that the volcano is especially active at this time.
Popocatepetl is the second-highest volcano in Mexico, located on the Pacific Ring of Fire and the Trans-Mexican Volcano belt. It was dormant since the 1950s before becoming active in 1994 — erupting occasionally with sometimes damaging results.
A large eruption in December 2000 caused mass evacuations of the Puebla state area around the volcano, although accurate prediction of the blast ensured that no one was hurt.
Volcano watchers can view a Mexican webcam stream of the volcano at this location. Tuesday, the webcam showed white smoke issuing from a seemingly quiet cone.