Four miles of tacks on U.S. 30 punctured bike riders' tires and injured at least one person Sunday, said M.J. Kelly, communications director of

. The tacks -- the source of which is still unknown -- were on the highway between Scappoose and Northwest Cornelius Pass Road, along the route for the

.

One rider fell because of the tacks, was knocked unconscious and was taken to a local hospital, Kelly said.

Many rode on undaunted, however. Some patched their tires with the repair kits they were carrying, and some had spare tubes to replace the punctured ones, she said.

Kelly said she was not sure if the tacks had been reported to the police.

"We're disappointed that someone took it upon themselves to sabotage the people who were riding in the event," she said.

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