AUBURN, Wash. (AP) — Picketers are slowing trucks as tensions rise between striking Teamsters and replacement workers at the United Natural Foods distribution center in Auburn.

The company says it had to hire some permanent replacement workers after members of Local 117 walked out Monday. Union members agreed to return Wednesday as talks continued, but they walked out again Thursday over the replacement workers.

The union says 72 warehouse worker have been replaced. The union represents 163 warehouse workers and drivers at the Auburn center.

More contract talks are scheduled Thursday.

Rhode Island-based United Natural Foods supplies organic foods to grocery stores.