LIVE: 'Kayaktivists' take to water to block Polar Pioneer as oil platform leaves port, arrests made

SEATTLE - Anti-Shell Oil activists took to the waters of Elliott Bay Monday morning, to try and blockade the "Polar Pioneer" rig platform as it moved from Elliott Bay.

Thirteen protesters got into kayaks and headed toward the oil rig that's been at Terminal 5 on Harbor Island, according to a press release from Greenpeace.

"The activists have secured themselves in place with enough supplies to last for hours while additional protests take place on shore," Greenpeace said.

Seattle Police and US Coast Guard are monitoring the situation. By 7:10 a.m., at least 10 activists had been detained by the U.S. Coast Guard.

This is a developing story and will be updated in our live blog below.

WATCH LIVE: A Greenpeace sponsored live stream of the protest from the water.