UPDATE 1-Greenpeace protest targets Syncrude oil sands mine

(Adds comments from Syncrude, Greenpeace, updates with arrest of 11 protesters)

CALGARY, Alberta, July 24 (Reuters) - Greenpeace protesters targeted a waste-water pipe at a Syncrude Canada Ltd oil sands project on Thursday, demanding a halt to rising crude production in the region, which they say is devastating the environment.

Greenpeace said in a release that protesters put a cap on the pipe to a toxic waste-water pond at the Aurora North mine at Syncrude's project site near Fort McMurray in northern Alberta.

They also raised a banner that read "World's Dirtiest Oil: Stop the Tar Sands," and put a skull-and-crossbones flag atop yet another pipe into the tailings pond.

Syncrude said the incident did not interfere with its operations, but added that the protesters broke into the area though a locked gate.

"While we encourage debate and dialogue about the environmental impacts of oil sands development, we do expect it to be conducted in a lawful and professional manner," Tom Katinas, Syncrude's chief executive said in a release.

Greenpeace said 11 protesters were arrested by police, ticketed for trespassing and released.

The environmental group is calling for the Alberta government to stop approving new projects to exploit the region's massive oil sands, which hold the biggest petroleum reserves outside the Middle East.

Oil companies are expected to spend more than C$100 billion to nearly triple production from the region -- to more than 3 million barrels day -- by 2015.