Police sources tell us the incident began after 1 p.m. with a large fight between males and females on the 3400 block of Tampa Street in Kensington.
During the confrontation, a female took out a gun, and then a male grabbed it and started shooting.
"I heard like three shots. I look out the window and see this guy running down the street here," said Mark Noble.
Police sources say a witness and others began running a block away into a house on Crystal Street. That's where the 59-year-old victim was shot in the chest while the suspect fired from outside the house.
Hours later, police and SWAT surround a home on the 1300 block of St. Vincent Street for a barricade situation.
They took a person of interest in for questioning but has since been released. Police also towed the person's white Buick for evidence, and got search warrants for the property and the vehicle.
Police sources tell us they're still looking for at least one more person of interest.
No weapons were recovered at the scene.
The victim was identified as Gladys Rivera-Perez.
Anyone with information is asked to call police at 215-686-TIPS.
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