CHICAGO -- Chicago police are questioning a person of interest as they investigate a deadly fire on the city's South Side.
Four people, including three young sisters, died in the blaze at an apartment building near 81st and Essex in the South Chicago neighborhood.
Fire investigators suspect arson.
The Chicago Fire Department says it's getting help from federal agencies, and the ATF will utilize a specially trained dog that can detect accelerants.
One resident says a man who lived down the street intentionally set the fire after he argued with her over money.
Flames consumed the second and third floors of the building just before 2 a.m. Tuesday.
One man was critically injured when he jumped from a third floor apartment with his 3-month-old daughter in his arms.
The baby's sisters, ages 4 and 7, were found in their burned out apartment.
Friends and relatives of the girls gathered at the building Tuesday night for a vigil.
The identity of the man who also died in the fire has not been released.
EquityBuild CEO & Chairman Jerry Cohen and EquityBuild President Shaun Cohen released a statement on Tuesday, which states in part:
"Our hearts are breaking over the deaths of four members of our extended EquityBuild family in a fire caused by arson, last night at our building located at 8100 S. Essex Avenue in Chicago. This senseless act of one individual is a profound tragedy.
Three sisters, Shaniya Staples, age 7, Madison Watson, age 4, and 3-month-old Mellanie Watson, died last night, along with an adult man whose name has not yet been officially released. Others were also injured in the fire, building residents and Chicago firefighters. They are all in our prayers, along with their families. Our hearts go out to them.
Also, building residents have been displaced just as school is about to start. Our Chicago-based team is working aggressively with our property manager to provide housing for them. And we are working with the Red Cross to help provide clothing and support."