LAKE WALES, Fla. -- A woman who was set on fire during a robbery of a Polk County insurance office last week died on Tuesday night, according to authorities.

Yvonne Bustamante, 26, died at about 10 p.m. after suffering burns over 80 percent of her body.

Juanita "Jane" Luciano, 23, who is Bustamante's sister-in-law, was also set on fire during the incident, remains in critical condition, authorities said.

Luciano's baby, who was delivered by Caesarian section after the incident, died Thursday night at an Orlando hospital. The baby, who was born more than three months premature, weighed 1 pound, 2 ounces.

A man who attempted to help the women was shot in the nose, but he's OK, police said.

Leon Davis Jr., 30, was charged in the incident and officials said they believe Davis killed two employees of a BP gas station in another Polk County city on Dec. 7.

Davis was linked to the slayings when the bullets taken from the two gas station victims matched bullets fired during the attack on the two women.

Davis has been charged with attempted murder, kidnapping, arson and armed robbery, and officials said more charges, including first-degree murder, could be filed against Davis as early as Wednesday.

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