The Popocatepetl volcano spews ash and steam as seen from Santiago Xalitzintla, Mexico, Friday, May 17, 2013.

The Popocatepetl volcano spews ash and steam as seen from Santiago Xalitzintla, Mexico, Friday, May 17, 2013. Seismic activity has increased at the Popocatepetl volcano near Mexico City, leading authorities to alert towns in two central states and the capital. Popocatepetl has put out small eruptions of ash almost daily since a round of activity began in 1994. (© AP Photo/Eduardo Verdugo)

MEXICO CITY (AP) — The Popocatepetl volcano near Mexico City is still rumbling.

Mexico's National Disaster Prevention Center says seismic activity shook the area early Sunday. And the 17,886-foot (5,450-meter) mountain also emitted gas, ash and glowing-hot rocks.

The snow-capped volcano has been erupting periodically since 1994 and eruptions began strengthening about two weeks ago.

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