OLD TOWN — An extra-alarm fire at an Old Town building "destroyed" the offices of Chicago's iconic Second City Theater Wednesday, fire officials said, and it is now extinguished after more than two hours and two injured firefighters, fire officials said.

The blaze started about 1:20 p.m. as a grease fire in the kitchen of Adobo Grill, which is on the ground floor of the building at 1612 N. Wells, according to the Chicago Fire Department. The fire was "under control" as of 3:42 p.m. and "struck out" at 3:55 p.m.

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Crews remained on the scene Wednesday evening as firefighters drained water out of the building.

Draining the water out of the building. It's a ton of water. @DNAinfoCHI pic.twitter.com/q92zUtiU21 — Mina Bloom (@mina_bloom_) August 26, 2015

About an hour after the blaze started, two firefighters were injured and the offices of Second City were "destroyed," fire officials and witnesses said on Twitter. The offices are located on the second and third floors of the building, but the theater itself is next door.

CFD spokesman Larry Langford said the firefighters were in "stable" condition and that their injuries were not serious. Another person on the scene suffered minor smoke inhalation, Langford said.

CFD spokesman Larry Langford explains how the fire spread:

Langford said smoke from the restaurant stove went up the building's vent, which prompted the roof blaze.

"[There's] a lot of old wood up there," Langford said. "The building itself is way over 100 years old."

At first, the fire department thought the fire would be contained quickly, but according to department tweets the blaze escalated when the roof caught fire and partially collapsed.

"There's smoke in Pipers Alley," Langford said, referring to the former theater that currently houses a gym, a Starbucks and other shops at 1616 N. Wells St., next door to where the fire broke out. "The fire got into Pipers Alley a little bit. Crews put that fire out so Pipers Alley is safe."

He added that the Second City Theater building that houses the famed comedy club's stages adjacent to Piper's Alley, which was evacuated around 1 p.m., was safe. Wednesday evening, CFD reported Second City Theater was in "good shape" and there was a small amount of water in the lobby and other areas.

second city theater area in good shape small amount of water lobby and other areas sustained damage pic.twitter.com/8y9MbZ00nu — Chicago Fire Media (@CFDMedia) August 26, 2015

Theater looks good! pic.twitter.com/R3bHxYEzAc — Chicago Fire Media (@CFDMedia) August 26, 2015

Second City reported that everyone was safe.

Katie Rich, a writer for "Saturday Night Live" and main stage alum at Second City, tweeted "My clubhouse is on fire" Wednesday when she heard the news.

All classes and shows scheduled for the Old Town venue Wednesday were cancelled, and the theater announced that box office reps would contact ticketholders with further information.

The city's other improv hub, the iO Chicago theater, opened its doors to Second City box office staffers who rushed to cancel the evening's shows.

UPDATE: All Second City faculty and training center campers have been safely evacuated. Stay tuned for more info. pic.twitter.com/BohRT3NK9N — The Second City (@TheSecondCity) August 26, 2015

As of 3 p.m., North Avenue was still closed at Wells Street and No. 72 CTA buses were also being rerouted.

Mina Bloom reports from the scene of the Old Town fire:

Ald. Brian Hopkins (2nd), who represents a small portion of Old Town that encompasses Piper’s Alley area, was on the scene of the fire on Wednesday.

Hopkins said he has been in touch with Adobo Grill's building owner, Thomas Tully, who Hopkins said is a former Cook County Assessor in the 1970s and local attorney who owns several properties.

The Queen Anne-style apartment building that houses Adobo Grill and Second City's offices dates back the 1880s and is considered to be an orange-rated building, meaning it possesses some historical importance and would not be able to be demolished without an evaluation or delay period under a special ordinance that protects old buildings.

"It is in serious condition, it might not be able to be saved; we might lose a very important part of the Old Town community," Hopkins said.

In a odd twist of events, Hopkins had spent his morning on Wednesday enrolled in a "Firefighter for a Day" training program for aldermen, where he was on his hands and knees crawling through a simulated smoke-filled room

"It's physical and one of the hardest jobs; these guys are real heroes," Hopkins said of the firefighters.

In June, Second City announced plans to expand into the former AMC Loews Theater space in the building, a 25,000-square-foot addition that was set to double the theater's footprint, adding new classrooms, two student theaters, a screening room, student resource center, bar and special events area.

Langford said the "structural work" being done at Piper's Alley had nothing to do with the fire.

Aerial look at damage to @TheSecondCity offices above Adobo on Wells. #Skycam9 pic.twitter.com/y61VUCSMF1 — Sarah Jindra (@SarahJindra) August 26, 2015

Flashback: Chicago firefighters work a blaze at Piper's Alley on March 1st, 1971. pic.twitter.com/AauipbtQme — CWBChicago (@CWBChicago) August 26, 2015

Roof is still going. Some collapse of roof in progress no injury. Second city still good pic.twitter.com/TKm3dCIb7W — Chicago Fire Media (@CFDMedia) August 26, 2015

New flames West of the tower. Yikes. pic.twitter.com/XN7DPP9mmk — Holmes McHolmester (@bhomey) August 26, 2015

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