UPDATED: Alliston’s Walmart store remains closed and it is unknown when it will reopen after multiple fires were set inside the Dunham Drive location on April 7.

The Nottawasaga detachment of the OPP charged a 15-year-old girl with arson in connection with the fires. Police believe the suspect hid inside the store when it closed at 10 p.m.

"There was multiple fires set," Const. Lisa Cruz confirmed.

New Tecumseth firefighters responded to the fires at about 11:50 p.m. on April 7 and extinguished a fire in the central area of store. The sprinkler system inside the store engaged, helping to extinguish the flames.

Related Content Barrie employee has rough start to first day on the job

Investigators from the Office of the Fire Marshall and members of the OPP Forensic Identification Unit also attended.

There was heavy smoke inside the building, according to police. Cruz said the store was searched to ensure no one else was inside and that there were no injuries.

It is unknown when the store will be set to reopen, according to Walmart Canada.

"We have to continue to assess the damage and determine what inventory needs to be replaced," said Alex Roberton, senior director of corporate affairs for Walmart Canada. "We need to make sure we don’t offer the customers anything that could put their health at risk and also make sure the store is safe to work in for our associates and our customers."

Roberton said they do not have an estimate on the amount of damage done yet or know what inventory will have to be replaced.

“We’ll know once we’re finished doing the damage assessment what needs to happen," he said.