LAKEVIEW — Residents of a Lakeview condominium building are outraged that an alley fire that ravaged their homes might have been set intentionally.

Three days after the fire left the 3046 N. Sheffield Ave. building water-logged and burned out, security footage obtained by DNAinfo Chicago shows three people in the alley just minutes before the fire erupted.

Two of the people pause at the trash cans for about a minute and a half, during which their activity appears to cause brief flashes.

Garbage can fires happen "more often than you'd think" and can have purely innocent causes, said Chicago Fire Department investigator Victor Megaro. After DNAinfo Chicago brought the video to the attention of the Fire Department, Megaro said it would "go the next step" and involve arson detectives.

Chicago Police Department News Affairs said it was unaware of the situation, and the Town Hall District declined comment.

What appears to be the remains of a blue recycling bin is among rubble from a house fire at 3046 N. Sheffield Ave. [DNAinfo/Ariel Cheung]

Mike and Meredith, a couple who live in the building and are expecting a baby in September, felt "completely, completely violated" when they saw the video on Wednesday, Mike said.

"It's horrible to watch, just seething with anger. It quickly ramped up the feelings from sadness about our house to confusion to anger. These guys could have easily killed all three of us, not including the baby," Mike said, referring to his family and his neighbor Simon.

The residents have requested their last names not be published, as they have no idea who the men are or what motivated them if they did intentionally start the fire.

"It's one of those things where you ask the, 'Why me?' Was there some sort of malicious intent specifically to us or the building, or was it just random?" Mike said.

A fire that started in garbage bins in the alley behind 3046 N. Sheffield Ave. has left homeowners stranded, including a pair of expectant parents. [DNAinfo/Ariel Cheung]

Mike and Meredith woke up around 4 a.m. Monday to the beeping of a fire detector in the fire escape that separates their home from Simon's.

When the couple went to investigate, they found the entire side of the building was on fire. Within minutes, firefighters arrived, and the fire was out by 4:15 a.m.

While Simon and Mike assumed the fire had sparked in the trash and recycling bins next to their building, they never thought someone would intentionally endanger them until a neighbor came forward with the video.

At 3:52 a.m., one man walks through the alley and is followed by two others, who pause at the trash cans on the alley-facing side of the building for over a minute. The two men kneel by the cans, make movements that cause brief flashes of light.

After pausing by the trash cans for about a minute and a half, the two men walk away in the same direction as the first man. At 3:54:33, one man glances back toward the trash cans.

The fire occurred very near the area where at least two suspicious fires were set last year. The Crime in Wrigleyville + Boystown blog covered the slew of fires extensively.

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