Three firefighters were injured in the early morning three-alarm blaze that tore through a vacant building on Kensington Avenue in Jersey City and jumped to a nearby home, a city official said.

While all three firefighters were initially taken to Jersey City Medical Center-Barnabas Health, two were later transported to St. Barnabas Medical Center in Livingston to be treated for burns, according to Carly Baldwin, a spokeswoman for the Jersey City Public Safety Department.

Both firefighters are currently undergoing treatment for those burns "as part of standard procedure," Baldwin said.

The other firefighter suffered shoulder and back injuries when he fell through a hole in the building, and was treated and released from Jersey City Medical Center, Baldwin said.

The fire, which started at a vacant house at 188 Kensington Ave., was first reported at 1:57 a.m. The blaze was under control by 3:30 a.m., but not before jumping to a two-family home next door, displacing one resident, Baldwin said.

When firefighters arrived, they battled "heavy, heavy" flames, which later caused a partial roof collapse at 188 Kensington Ave., Baldwin added.

Jersey City fire officials believe squatters were living in the building and fled the scene as soon as the fire started.

Tom Karczewski, who lives on the first floor of 186 Kensington Ave., said his mother used to live on the second floor of the home, but recently moved to hospice care in Jersey City.

"Thank God my mother wasn't there," said Karczewski, 55.

The top floor of Karczewski's two-story home caught fire as flames leaped from the blaze next door. Scorch marks and melted siding can be seen on the side of the home. Several windows are broken out, Karczewski says that they broke when hit with the force of the water from the fire hose.

Karczewski was sleeping in his first floor apartment when he heard a man in the street yelling, "Fire! Fire!"

When Karczewski came outside he saw overhead wires falling into the street and sparking as they hit the ground.

"The firemen did a great job," said Karczewski. "It would have been much worse if not for them."

Both Karczewski and George Vega, 44, who lives in the apartment building next to 188 Kensington Ave., believe that it has been vacant for at least a "couple of years."

Karczewski was told he could stay in his apartment, but has chosen to stay with his brother for the time being.

Meanwhile, Baldwin said the firefighter who was treated for shoulder and back injuries fell through a preexisting hole in the home's living room near the front door.

Baldwin added that the city's vacant buildings are undergoing a series of inspections by the Fire Department to account for holes like the one at 188 Kensington Ave. and other kinds structural instability.

A five-story apartment building at 192 Kensington Ave. was evacuated last night as a precaution, although residents were allowed back in, Baldwin added.

Journal staff writer Patrick McGovern contributed to this report