Surrey RCMP say the pair noticed a man lurking in a restricted area at the rear of the eatery and thought he might be preparing to steal something.
They had noticed him hanging around earlier said police.
When they confronted and tried to detain him, police say the man grabbed a kitchen knife and slashed at them.
One of the workers was stabbed in the abdomen, the other in the arm.
Police say they are still looking for the assailant who escaped.
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