The union representing 10,000 striking Air Canada flight attendants said Sunday it will challenge an order for them to return to work, adding "we remain on strike." The Canada Industrial Relations Board ordered airline staff back by 2 p.

Air Canada flight attendants said on Sunday they will remain on strike and spurn a government return-to-work order they called unconstitutional that would send them back to their duties by 2 p.m. ET (1800 GMT).