AN IMMINENT volcanic eruption will devastate Iceland with just 30 minutes' notice, scientists have warned.
Almost 4,000 people have already fled the coastal town of Grindavik following thousands of rumblings which left roads cracked and buildings damaged.
The residents were ordered to evacuate on November 11 as magma began to shift beneath the Earth's crust.
New drone footage from CNN showed inside the massive crater from which experts believe lava will soon spew, as weeks of seismic activity come close to a halt.
Only 165 tremors have been recorded in the past week - a dramatic drop from the thousands recorded in the week prior - which some say could be an indication the volcano is ready to erupt.
But the Icelandic meteorological office said on Wednesday evening it considered the probability of a sudden eruption to be "low" and "decreasing every day" due to declining magma flow and seismic activity.
Authorities announced the state of emergency in place since November 11 would be lifted on Thursday at 11am GMT and residents would be allowed to return to the town to collect their belongings.
Other CNN video showed large gashes in the roads and grounds of Grindavik essentially splitting the town in two.
The Icelandic Meteorological Organisation, which believes an eruption could happen with just a 30-minute warning, declared on Tuesday that the volcano's "danger zone" had been expanded.
A map showed three "danger zones": one large zone, coloured orange, where there is danger due to seismic activity, one smaller zone, coloured red, where there is danger due to sudden eruption, and one even smaller zone within, coloured purple, where there is an increased danger of eruption, and of it occurring suddenly.
Icelandic authorities are now considering using water to cool and divert the flow of lava and protect the beloved fishing town on the country's southern Reykjanes peninsula.
The "high-volume pumping" method was employed in 1973 when a fissure erupted just 150 metres from the town centre on the Icelandic island of Heimaey, allowing residents to slow and control the spread of lava.
Preparations are also now underway to build defence walls around the town's geothermal power plant to protect it from lava.
The Svartsengi geothermal plant is the main supplier of electricity and water to 30,000 residents on the Reykjanes peninsula.
Iceland's head of civil protection and emergency management Vidir Reynisson told reporters on Wednesday: "An assessment technical team will arrive in Iceland tonight or tomorrow morning and they will assist us in assessing the possibilities."
A senior lecturer in Earth sciences, Margaret Hartley, said earlier this week that eruption will occur when magma breaks through the Earth's surface.
She explained: "The process is a bit like shaking up a can of fizzy drink - as soon as a crack opens in the top of the can, the drink escapes with lots of frothing.
"I do think an eruption will take place, but the big question is when that might happen.
";In these situations, things can change very quickly. If there is an eruption, it could occur even before we can predict it."
Iceland is home to 33 active volcano systems, the highest number in Europe.
The country experiences an eruption every four or five years, on average, but direct volcanic threats to residential areas are rare.
