The first crash came just after 12:15 a.m. Sunday at Front Street along The Boulevard.
According to investigators, five people from two cars were taken to the hospital with non-life-threatening injuries.
Officers have not said what caused this collision.
Then, just after 12:30 p.m. and roughly three blocks away, a red Nissan Pathfinder traveling northbound on the boulevard lost control and collided with a tree in the median.
Surveillance video caught the collision on camera.
Residents who live along the roadway described what they heard when the car crashed.
"Like a loud bang, crash, and skid, (and) the sound of the tires. It was real horrible, real horrible. Screams, everybody came out," one neighbor explained.
Police say three teenagers were inside the car, all of them 16 years old.
One teen was pronounced dead at the scene, while the others were hospitalized in stable condition, according to authorities.
Action News spoke with one woman who recounted her efforts to try and save the teenager who died.
"When I see him jump over here, I come running. The car was so fast, when I see the smoke I was almost close," said Teresita Jimenez from Feltonville.
Jimenez says she and other neighbors helped pull the teenagers from the car.
"I say, 'Is somebody more inside?' 'Yeah.' I cut the belt for him, broke the plastic to try and take him out. Check him, he had a little pulse. He died," she said through tears.
Residents in the area say they have witnessed too many crashes on this stretch of the roadway.
"They call it 'killavard,'" one resident said. "I don't like that. No humor to it. It's sad, I've seen too many people perish here."
"It's just so much death out here in this boulevard. It's tiresome," the resident added.
Both incidents are currently under investigation.
Police say the driver involved in the fatal crash was taken in for questioning. There is no word yet on whether charges will be filed.