By Reg Chapman

PLYMOUTH, Minn. (WCCO) – The State Fire Marshall is trying to determine what caused an early morning apartment complex fire in Plymouth that sent dozens running for safety.

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A four-alarm fire engulfed the Vicksburg Village Apartments around 4 a.m. after it appeared that a window AC unit on the third floor started on fire.

Fire crews, after clearing a call nearby, were on the scene within minutes.

“We had a very advance fire upon arrival,” Chief Richard Kline said. “Our initial actions was to make sure we could get all the tenants out, which we did.”

Crews helped more than 60 tenants from their apartment homes — 12 had to be rescued by firefighters.

Others were able to get out on their own.

“I saw the smoke doors shut, and I went through the first smoke door and the entire hallway was just black solid smoke,” resident Susan Johnson said.

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Johnson was able to grab her dog and get out.

Plymouth Fire Chief Richard Kline says the building was built in 1990 and sprinklers were not required to be installed back then.

“If there had been a sprinkler system, we would not be having this conversation,” Kline said.

Without sprinklers, Kline said the burning apartments did not stand a chance.

“It’s all wood,” Kline said. “It’s a lumber yard and once it reaches that attic space and breaches that attic space — it’s a matchbox.”

No tenants or firefighters were hurt.

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Everyone in the complex had renter’s insurance, so companies have been assisting residents find alternative places to call home in the meantime.

Reg Chapman