Iceland's biggest volcano could be set to erupt after witnessing the biggest tremors in 40 years.
Early on Monday, two earthquakes of more than 4 in magnitude were recorded by Iceland's met office around the Katla volcano, rocking its crater and setting off a chain of tremors around Katla.
Many will remember the the eruptions of another Icelandic volcano, Eyjafjallajökull, back in 2010, which released a huge ash cloud and caused widespread disruption - even forcing the Barcelona football team to switch to train travel for their Champions League semi-final against Inter Milan.
So will Katla - which is named after an evil troll - erupt? And if so, how much destruction will it cause?
Gunnar Gudmundsson, an Icelandic geophysicist, appeared untroubled by the prospect, saying on Monday there was "no sign" of an eruption, although he did describe the current situation as "a little bit unusual."
This certainly isn't the first sign the area around Katla has witnessed an earthquake; indeed a number of quakes have already been recorded this year.
Jon Frimann, who runs his own blog on volcanoes and volcanology, told talkRADIO that the flurry of earthquakes in the area doesn't mean anything at the moment, although "lack of good data on what happens in Katla prior to an eruption makes it difficult to figure out what is happening."
Frimann did say that "Katla is going to erupt in the end. It has an average period between eruptions of around 80 years. Some periods are shorter - they can go as short as 13 years between eruptions - and others are longer. The current one is a long one, going 98 years."
Frimann told us that when Katla does erupt, the impact will be several times larger than the eruption of Eyjafjallajökull. However he qualified this by saying that the 2010 eruption was actually a relatively minor one, and there is no real way of knowing how big an eruption of Katla would be.
"The most damage [would be to] bridges and roads due to massive glacier flooding that comes from the Mýrdalsjökull glacier, which is on top of the Katla volcano," Frimann said. "An eruption melts up to 300 meters of glacier on top it, resulting in massive floods with glaciers that are massive in size. Mud and other debris is also going to be a big problem in the long run."
Speaking about the possibility of a new ash cloud, one which could potentially impact the UK, Frimann said: "There is going to be an volcano ash cloud from an eruption in Katla, how far and how big it is going to be depends on the eruption and it's impossible to know how that plays out before an eruption happens.
"If an ash cloud from Katla is going to have an effect on UK depends on the wind direction when the eruption starts. I would expect some problems to appear following an eruption in Katla, ash clouds are always a problem for air-plains, how much of a problem depends on the weather that day."