WINNIPEG, Manitoba -- A Canadian independent truckers group, frustrated with higher costs and increased competition from the United States, have blocked two international border crossings in Ontario, Canadian transportation industry officials said yesterday.

David Bradley, vice president of the Ontario Trucking Association, told Knight-Ridder Financial News that the blockades by the independent truckers started yesterday morning. He said he did not know how long the blockades would last.

The Ambassador Bridge that connects Windsor with Detroit and the Lewiston-Queenston Bridge at Niagara Falls were blocked to truck traffic, but passenger traffic was getting through, he said.

Truckers are protesting the Canadian government's lack of action in dealing with increased competition from the United States after the Canadian trucking industry was deregulated three years ago, said Ken Macleren of the Canadian Trucking Association.