Updated 11/6/11 – 6:10 p.m.

CHICAGO (CBS) — It was a simple trip by three acquaintances to pick up a cake at a South Side bakery, but minutes after doing so, all three people were shot dead inside a car in the parking lot.

It happened Saturday night on the 400 block of East 87th Street.

As CBS 2’s Dana Kozlov reports, police were talking to a “person of interest” about the triple murder in the parking lot outside A Piece of Cake bakery and a neighboring Church’s Chicken restaurant.

The Sun-Times Media Wire reported the person of interest being questioned is a teen. Witnesses picked a 17-year-old Chicago boy out from an array of photos as the person who allegedly shot the three who were all sitting inside a car, police said. No charges had been filed.

Police said a car drove up to the parking lot at about 5 p.m. Saturday, just as a woman was leaving the bakery and getting into the parked car with two men.

That’s when someone inside the passing car opened fire, killing the three people in the parked car.

Witnesses said a man pulled the trigger and then bystanders ran over to help the victims.

“It looked like he knew them,” said eyewitness Valerie Durham. “I don’t think it was a random thing that happened like that. It really doesn’t make any sense for someone to come out of a bakery getting a cake and someone just walk up and shoot.”

Police said the woman and one of the men were dead on the scene. Authorities said the second man was initially taken in critical condition to Advocate Christ Medical Center in Oak Lawn, where the medical examiner’s office said he was pronounced dead at 7:05 p.m.

chanda Cops Questioning Person Of Interest In Triple Murder In Chatham

Chanda Thompson (CBS)

One of the men was identified as Cortez Champion, 21, of 9105 S. Harper Av., according to the Cook County Medical Examiner’s office. The female victim was identified by a friend as Chanda Thompson, 21.

Officials have not yet released the other two victims’ names, but police said the three victims are not family members.

Police also said the victims were not robbed.

“It was just a tragedy, you know, just to see them people sitting in that car, trying to breathe in their last breath,” said Jennifer Lias, an assistant manager at the Church’s Chicken.

A bakery worker said the woman who was killed had picked up a birthday cake for her daughter’s 2nd birthday on Sunday.

The bakery has been operating in the Chatham neighborhood for 30 years, according to its website.

Former Mayor Richard M. Daley stopped there for a piece of birthday cake emblazoned with his picture last April while making his farewell tour of the city.

(The Sun-Times Media Wire contributed to this report.)

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