JERSEY CITY, N.J. (CBSNewYork) — Authorities say they are looking for a person who was seen fleeing the scene of a massive fire at a multi-family home in Jersey City that left a man critically hurt and a baby hospitalized.

Arson investigators Thursday were focusing their attention on the lower level of 21 Grant Avenue, where they say the 4-alarm fire began just after 7 p.m. Wednesday.

Mamie Givens lives across the street and watched in panic as she saw her frightened neighbors racing out.

“I saw the smoke coming from the basement,” she told CBS2’s Janelle Burrell. “Then all of a sudden, I did see the flames”

Crews used multiple hoses to battle the smokey conditions and get the flames out.

“Fire was in the basement upon arrival, heavy fire, heavy fire load in the basement also, difficulty getting in there,” said Jersey City Fire Chief of Department Steven McGill.

Officials say the fire quickly traveled through the walls to the upper floors.

“I goes in the hallway, look over the balcony and there’s a lot of smoke,” said fire victim Dwayne Shurn. “I run back in the house and tell my family, ‘Lets go! Get your coat or shoes or whatever and let’s get out this house right now.'”

Authorities said a man was rescued from the basement. He was taken to the hospital in critical condition with burns to nearly 20 percent of his upper body. Fire officials say they are now looking to talk to another man who was with him.

“The other male got out, took off,” said McGill. “We’re trying to find him. Our arson investigators are looking to question him.”

A 6-month-boy was also rescued from the burning home and was treated at the scene by firefighters before being taken to the hospital. A firefighter and another resident suffered minor burns and cuts.

Officials said 20 residents who were displaced by the blaze have been offered help by the Red Cross.

The scene was especially disturbing for longtime residents. An empty lot right across the street is where nearly four years ago, a well-known pastor, his wife and two sons were killed when a fire ripped through several homes on the block.

“This house and my house were gutted, destroyed,” said Givens. “So anytime there’s a fire on this block, it’s very disturbing to us.”

The cause of the fire is under investigation.

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