Canada's Nexen Energy said on Friday its crews were working "around the clock" to clean up a pipeline leak at an oil sands site in northern Alberta that is one of North America's largest environmental spills on land.
The wholly owned subsidiary of CNOOC Ltd said it detected the spill at its Long Lake facility on Wednesday afternoon. The pipeline leaked 31,500 barrels of emulsion, a mixture of bitumen, water and sand.
(Reporting by Nia Williams; Editing by Jeffrey Hodgson, Editing by Franklin Paul)