A volcano just south east of Mexico city has started to erupt, shooting rocks and plumes of ash nearly 4km high into the sky.
Popocatepetl, which is 5,400m high and one of the world's most active volcanoes, is just 37 miles from the capital.
It's not yet known how the latest activity will affect the 18 million inhabitants, but there are fears that an ash cloud could develop.
At the moment, the eruption is rated 'yellow phase 2', which means no one is allowed within 12km of the volcano.
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