Rock and ash have begun to spew from Guatamala's Fuego volcano.
The huge peak, one of the country's most active, has been relatively quiet recently, but over the last few days has become increasingly noisy.
According to geologists, lava flows over a kilometre long are trickling down the east and west of the mountain, whilst ash clouds are towering over 1,500m into the sky.
No evacuations have been ordered, but officials have alerted aviation authorities about the plumes of ash which could cause problems for air traffic.