More details:
This relates to both USA and Canada, as the "iroquois nation" resides within both countries.

"The U.S. government had said it would only let players back into the country if they have U.S. passports, a team official said. The British government, meanwhile, wouldn't give the players visas if they could not guarantee they'd be allowed to go home."


http://www.cbc.ca/world/story/2010/07/14/us-iroquois-lacrosse-team.html