Two Greenpeace activists who scaled an oil rig off the western coast of Greenland at the weekend to protest oil prospecting in the Arctic were arrested overnight, police and the environmental group said Thursday. \"Last night, the police decided the time was right, and we arrested the two activists,\" Greenland deputy police chief Morten Nielsen told AFP. \"They are being transported to (Greenland capital) Nuuk, and it will be determined whether they they will go before a judge,\" he added. Greenpeace also said the two 25-year-old activists, Luke Jones of Britain and Hannah Mchardy of the United States, had been arrested after hanging in a \"survival pod\" beneath the 53,00-tonne \"Leiv Eiriksson\" platform for four days. \"Our climbers are in jail now, but this won\'t stop us opposing the madness of drilling for oil that we can\'t afford to burn and in a region where a spill would be almost impossible to clean up,\" Greenpeace international oil campaigner Ben Ayliffe said in a statement. The two activists had arrived by rubber dinghy early Sunday at the 53,000-tonne platform, which is due to begin drilling for oil 180 kilometres (110 miles) off Greenland for Scottish company Cairn Energy. The activists had remained in their survival pod, suspended from the underside of the rig, \"25 metres (82 feet) over the freezing Atlantic Ocean,\" until \"just before midnight last night, local time (0000 GMT Thursday),\" Greenpeace said. \"A climb team operating from the rig broke into the pod,\" the organisation said, adding \"Danish navy inflatable speedboats were positioned below the climbers\" and that it therefore believed the climbers were from the Danish navy. Deputy police chief Nielsen however said the operation was run by local police in Greenland, which is a semi-autonomous Danish territory, but that the Danish navy had been on sight in case rescue efforts were needed. \"When you\'re suspended that high above the freezing water it\'s good to have some help in case,\" he said. The two activists could face charges under Greenland\'s immigration laws, Nielsen said, adding it was unclear how quickly they would be presented before a judge. \"Under Greenland immigration laws, we have a right to detain them for 72 hours before they are presented in court,\" he explained. Ayliff, who was on the Greenpeace shop Esperanza near the rig and had seen the operation, insisted that despite the arrests of Jones and Mchardy, \"this isn\'t over.\" \"We must keep on pushing till the oil companies get out of the Arctic,\" he said in the statement. \"We stopped this rig from drilling for four days, which was four days in which a Deepwater Horizon-style blow-out couldn\'t happen in this beautiful and fragile environment,\" Ayliffe said. Four Greenpeace activists occupied a Cairn prospecting platform off Greenland last August, stopping drilling for about 40 hours before they were forced to abandon the protests owing to freezing Arctic weather conditions. Cairn Energy could not be immediately reached for comment on how the action had affected it preparations to begin production or whether it had pressured police to arrest the activists. Nielsen meanwhile said it was \"no secret\" that \"Cairn as an interested party wanted them removed.\" Greenland is looking to oil prospecting as a way to ensure its economic independence. The Arctic seabed is thought to hold about 90 billion barrels of oil and 30 percent of the world\'s undiscovered gas resources, according to the US Geological Survey.