MEXICO CITY â€"  The Popocatepetl volcano is shooting a heavy plume of ash into the sky southeast of Mexico's capital, and television images show a reddish glow near the crater.

Webcam images on the site of the National Disaster Prevention Center show the plume rising from the top of the 17,886-foot peak at dawn, though clouds obscured the volcano for people further away.

The Televisa television network broadcast images of red, glowing material near the crater.

Authorities this week raised the alert level due to increasing activity at the volcano, whose most violent eruption in 1,200 years occurred on Dec. 18, 2000.