By: KDKA-TV News Staff

PITTSBURGH (KDKA) – A man has been arrested for the massive fire that destroyed a historic building on the South Side in February.

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Pittsburgh Police say a joint investigation between the city’s fire investigation unit and ATF resulted in the arrest of 25-year-old Christian Ross on multiple arson-related charges.

(Photo: KDKA Photojournalist Ian Smith)

According to the criminal complaint, investigators said Ross was a former tenant who moved out of the building. The property manager told police Ross moved out without returning his keys and broke back into the building on numerous occasions.

On Feb. 8, the day of the fire, investigators say Ross was let back into his apartment to retrieve some belongings.

Investigator said Ross, who was not supervised while getting his belongings, was caught on surveillance video on multiple floors of the building before leaving out the backdoor with a suitcase. On May 12, according to investigators, Ross confessed to setting the blaze while in jail on unrelated charges, saying he bought a handheld torch to start the fire.

The criminal complaint says the first evidence of fire came 16 minutes after Ross left the building.

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(Photo Credit: KDKA)

District 3 City Councilman Bruce Kraus said the building at the corner of 11th Street and East Carson Street dated back to 1874. Naturally, being on East Carson Street, it was a bar at one time.

The more than century-old building had been restored with six apartments and two businesses: a barbershop and the South Side Chamber of Commerce.

The building partially collapsed after firefighters doused the building with water and it was later demolished. No one was injured.

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Ross is currently already behind bars in the Allegheny County Jail on separate charges. Other charges in this case include nine criminal mischief charges and a count of causing catastrophe.