It happened around 5:30 Saturday afternoon on the 1100 block of Upland Street.
Police say a house was riddled by gunfire and numerous shell casing covered the street within a two block area.
An anonymous neighbor on the block describes how she took cover.
"I just jumped on the floor of my bedroom. My front door was open, I had to crawl down the steps and shut the front door and run back upstairs that's how long it took for the gunshots to stop," she said.
The woman tells Action News she used her own car to get one of the victims to the hospital.
"He was real calm, I was surprised he was very calm but his leg was bothering him," she said.
All four victims were taken to Crozer-Chester Medical Center for treatment.
A 17-year-old male was shot in the head and died from his injuries.
Family members tell Action News his name is Darren Burton and his nickname is "Jesse."
Two other teens were also struck. A 16-year-old is in stable condition and an 18-year-old is in serious but stable condition.
Authorities say the fourth victim, a man in his 40s, was an innocent bystander. He remains in critical but stable condition.
Police believe the three teenage victims were the intended targets.
The Chester police commissioner is taking a firm stance against violence in his city.
"We intend to see that the city is not taken over by some gun-toting thugs," Commissioner Joseph Bail said.
Commissioner Bail says police are reviewing surveillance video to help determine exactly what happened.
On Saturday night, distraught family members came to the hospital to support their loved ones.
However a heated turnout forced the hospital to shut down its emergency room entrance and only allow patients to enter.
Police officers were also forced to stand on guard at the hospital.
Chester Mayor John Linder says he's feeling for the victim's families but adds that the violence in Chester must stop.
He pleaded for people to come forward to police with information.
"Continue to help us, when citizens help us we can find out who these perpetrators are. It was broad daylight, somebody saw something that can help us so if you saw something please say something," said Mayor Linder
A motive in the shooting is still unclear. Police are looking for a deep burgundy colored Ford Escape with Pennsylvania tags which they believe is related to the crime.
The people inside the SUV are believed to be armed and dangerous.
Anyone with information is urged to contact Chester Police Detective Todd Nuttall at (610) 447-8426 or CID Detective Adam Sendek (610) 891-8030.