About 60 employees at the Amalgamated Dairies Ltd. plant in Summerside had to evacuate around 12:30 p.m. Thursday because of smoke in the building.
Plant CEO Jim Bradley said the problem was on the roof.
Bradley said there was no open flame, but it was smouldering so the building was evacuated as a precaution.
Summerside firefighters arrived quickly, but Bradley said it took time to track down the source of the smoke.
A 3-metre by 3.7-metre section of the roof was damaged.
Bradley said the plant does maintenance during the day on Thursdays so no milk was in production.
Employees were out of the building for about an hour.
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