MONTREAL - About 80 people took part in a vigil in downtown Montreal Saturday evening to denounce what they consider disproportionate punishment meted out against 30 Greenpeace activists detained in Russia.

The Russian Coast Guard seized the Greenpeace ship Arctic Sunrise and all the people aboard – including Canadians Alexandre Paul of Montreal and Paul Ruzycki of Port Colborne, Ont. -- following a Sept. 18 protest at an offshore platform owned by Russian state-controlled energy firm Gazprom.

Nicole Paul, whose son Alexandre Paul, 35, is among those detained, was at the event pleading to Russia to release her son.

Paul is one of 30 Greenpeace activists in preventative detention now facing up to 15 years in prison on charges of piracy.

The charges result from a demonstration on the Gazprom oil rig in the Arctic in which 28 Greenpeace activists, a photographer and videographer were arrested by the Russian authorities.

They are currently being held in a prison in Murmansk in the far northwest of Russia.

Jean-François Lisée, the PQ MNA with responsibility for international relations, gave a speech expressing support for the Paul family.

“The legality of the arrest is questionable and especially the charge of piracy, is clearly exaggerated.”

He pleaded with the Russians to show mercy.

Greenpeace denies any wrongdoing and has described the charges as absurd.

A similar vigil was also held in Port Colborne, Ont.,, the hometown of Paul Ruzycki.

"It's just totally off the charts that this type of charge would be laid," said his sister Patti Ruzycki-Stirling.

The rallies are part of a larger series of protests staged by Greenpeace and its supporters around the world Saturday.

Ahead of protests in several British cities and other parts of the world, including Brazil, Greenpeace international's director Kumi Naidoo called Russia's seizure of the Arctic Sunrise and the arrest of its crew the worst "assault" on the group's environmental activist since 1985.

That’s when French operatives attacked the Greenpeace flagship “Rainbow Warrior” in New Zealand, because activists on board were going to protest against French nuclear tests. One person died in the incident.

Actor Jude Law was among several hundred people gathered Saturday for a demonstration in London, England, where he said Russia's decision to charge the activists with piracy was "ludicrous."