NEW YORK (AP) — A fire broke out late Wednesday at an Amazon facility in upstate New York that’s voting in a union election next week.

The fire at the warehouse, located near Albany in the town of Schodack, began around 10:50 p.m. and lasted until shortly after midnight, according to Schodack police . It’s the third fire at an Amazon warehouse this week.

Amazon described the incident as a small fire contained to a compactor located just outside the doors of a loading dock.

Responding agencies stopped the fire from spreading to the structure of the building, Schodack police said. They said the fire was likely caused by mechanical failure. Workers were evacuated and no injuries were reported.

Fire department officials declared the building safe following a preliminary investigation, Amazon said.

“Out of an abundance of caution, we sent night shift employees home with pay and canceled Thursday’s day shift,” Amazon spokesperson Paul Flaningan said. The workers whose shifts were canceled will also be paid, he said.

In a tweet Thursday, the Amazon Labor Union said it was glad workers were given time off, but called it “simultaneously infuriating” the company suspended workers at another facility this week for demanding similar compensation.

On Tuesday, Amazon suspended dozens of warehouse workers who refused to work following a cardboard compactor fire at a facility on Staten Island that voted to unionize earlier this year.

Union organizers said day-shift workers at that warehouse were sent home with pay after Monday’s late-afternoon fire. Night shift workers didn’t get the same option, though many raised concerns the air wouldn’t be safe to breathe because of smoke and fumes resulting from the blaze.

Flaningan said on Wednesday that the company asked all night shift employees at the Staten Island warehouse to report to their shifts after fire officials certified the building as safe. But dozens refused and held a sit-down protest at the facility’s main office, demanding to be sent home with pay.

Separately, another fire broke out Monday at a facility in Alabama.