LEBANON, Ore. -- Police have arrested a man on arson charges, accused of setting a fire Tuesday at the Walmart in Lebanon. 

Police said when they were called to the store at 12:49 p.m. for a report of pool chemicals on fire inside the store, employees had already started evacuating. 

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They said fire damage was mostly contained to one aisle, but the smoke contaminated a large portion of the store's interior. They later determined several chemicals had been mixed, which then ignited. 

Detectives said they quickly identified Joel Lee Reynolds, Jr., 49, of Lebanon as the suspect. They arrested him on Thursday without incident. He's facing charges of arson in the first degree and criminal mischief in the first degree.

Police said they've had multiple contacts with Reynolds. In 2018, they arrested him for theft at Walmart and he was trespassed from the store.

The estimated cost of damages isn't known. Walmart is still closed while a restoration company makes repairs.