Environmental campaigners have targeted Shell petrol stations over the company's plans to drill for oil in the Arctic.
Greenpeace activists are hoping to shut off petrol to at least 12 petrol stations in Edinburgh.
Around 100 petrol stations in London will also be targeted by the group's protest.
The first station targeted was the Shell garage in Edinburgh's Dalry Road, where they attempted to scale the roof.
Lothian and Borders Police confirmed five people suspected to have committed public order offences had been arrested at the Shell station. A spokesman said protests were also under way at Shell petrol stations in the Seafield and Maybury areas of the city.
A Greenpeace spokesman said the five arrested had been chained to the petrol pumps. A further two remained on the roof, the spokesman added. He said a handle attached to the main switch had been removed by protesters and posted to Shell's headquarters.
Shell is due to begin drilling at two offshore sites in the Alaskan Arctic in the coming weeks.
Greenpeace's Sara Ayech said: "The oil giant Shell is preparing, for the first time, to unleash a drilling fleet of huge vessels upon the fragile and beautiful Arctic, home of the polar bears. It's time to draw a line in the ice and tell Shell to stop. That's why today we're going to shut down all of Shell's petrol stations in the capital cities of London and Edinburgh. We've got dozens of people who will hit over 100 Shell garages throughout the day.
"An oil spill in the Arctic would be catastrophic for wildlife such as walruses and whales, and Shell knows full well that it would be impossible to clean up after such devastation. The Arctic must be saved and made a global sanctuary where oil drilling is banned."
A spokesman for Shell said: "Shell recognises that certain organisations are opposed to our exploration programme Offshore Alaska, and we respect the right of individuals and organisations to engage in a free and frank exchange of views about our operations. Recognising the right of individuals to express their point of view, we only ask that they do so with their safety and the safety of others, including the general public and Shell personnel, in mind. Shell has met with numerous organisations and individuals who oppose drilling offshore Alaska. We respect their views and value the dialogue. We have extended this same offer for productive dialogue to Greenpeace."