Thick, black smoke pouring out on to York Street late Friday night obscured the view of those calling 911 trying to direct firefighters to a fire witnesses couldn't find, officials said.

"They couldn't see from Walnut Street to the traffic light at York and Broadway because the smoke was so thick and black," said Hanover Fire Department Captain Tony Klousher. "And they couldn't tell where the smoke was coming from."

But when firefighters arrived at the scene, the fire was determined to be at 20 and 22 York St., at the abandoned Super Sub shop, and they quickly got to work, extinguishing the blaze within an hour.

The fire started in the rear of the first floor of the abandoned Super Sub shop, then spread to the empty second-floor apartments above at around 11:38 a.m., Klousher said. There is still no known cause of the fire, but the damage is estimated to be $75,000, he added.

Pennsylvania State Police Fire Marshal Patrick McKenna was on the scene early Saturday morning to investigate but couldn't be reached for comment.

Yellow tape remained at the front of the building Saturday, where the sub shop's shattered windows showed a charred and gutted interior.

Traffic was shut down on York Street from Broadway to Walnut Street until around 3 a.m. Saturday morning, Klousher said.

Both buildings were empty, and no one sustained any injuries, Klousher said.

At least eight other fire companies were called out to battle the blaze.

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