British Greenpeace activist Anthony Perret, who was held in Russia following a protest over the country's Arctic drilling, said he was "chuffed" to be released.
Greenpeace's Arctic Sunrise Twitter feed states:
Anthony Perret, got out an hour ago, tells us "Chuffed to be out, it's quite nice really". #FreeTheArctic30
Great news: Kieron Bryan, the second Brit, has been released on bail in St Petersburg #FreeTheArctic30
More top news
Schools in London, Brighton and Newcastle were among those closed after bogus security threats.
The World Health Organization said postponing the 2016 Games would not 'significantly alter' the spread of the Zika outbreak.
Employment Minister Priti Patel has launched a scathing attack on the government's 'chaotic' immigration controls.