The famous volcano, located some 60 kilometers (37 miles) southeast of Mexico City, has been showing signs of activity all year.

Government expert Ramon Pena however rejected the idea of emergency scenarios.

"A bit of lava rose up and when it hit the freatic layer the smoke cloud occurred," Pena said.

At 5,465 meters (18,000 feet) above the sea level the Popocatepetl, also known as "Don Goyo," is Mexico's second highest volcano.

The Mexican Army guards Popocatepetl, with approach restrictions to the crater on a 12 kilometers (seven miles) radius.

Another volcano, the Colima, located some 500 kilometers (310 miles) west of the capital, has also shown significant signs of activity, spewing smoke columns some 4,500 meters (14,700 feet) above the crater.