CHICAGO (CBS) — At least 51 people were shot in Chicago this weekend as of early, nine of them fatally, including a 15-year-old boy and a 17-year-old boy.

Meanwhile, a stabbing on the city’s West Side this weekend left a 5-year-old girl dead, while another woman was found stabbed to death in the North Branch of the Chicago River.

In fatal shootings, a 19-year-old man was shot and killed at 10:01 p.m. Friday in the 9400 block of South Vernon Avenue in the Roseland neighborhood. The man was walking with two other males through an alley when shots were fired, police said.

The victim was taken to the University of Chicago Medical Center in with gunshots to the chest and back and was pronounced dead at the hospital, police said. He was identified as Cornelius Talthus Jr.

At 4:09 a.m. Saturday, a 42-year-old man was at a gathering in the backyard of a home in the 7000 block of South Harper Avenue in the South Shore neighborhood, when a man walked around from the front of the home and shot him in the back, police said.

The man was taken to the University of Chicago Medical Center, where he was pronounced dead, police said. He was identified as Rayalecio J. Perman.

At 4:53 a.m. Saturday, police were called for shots fired in the 200 block of North Latrobe Avenue in the South Austin neighborhood. They found a 20-year-old man with gunshot wounds throughout his body.

The man was pronounced dead at the scene, police said. He was identified as Richard F. Soward.

At 11:10 a.m. Saturday, a 17-year-old boy was in an alley behind the 200 block of North Leamington Avenue in the South Austin neighborhood when two assailants came up, shot him, and then fled south on Leamington Avenue in a light-colored vehicle, police said.

The victim was shot in the upper torso and was pronounced dead on the scene, police said. He was identified as Avion Aldridge.

At 9:20 p.m. Saturday in the 11600 block of South Prairie Avenue in the West Pullman neighborhood, a 15-year-old boy was shot in the head and was taken to Advocate Christ Medical Center where he was pronounced dead, police said.

The victim was identified as Omar Alvarado. Police did not have further details.

Around 5 p.m. Sunday, a 20-year-old man was dropped off at St. Bernard Hospital, 326 W. 64th St., with a gunshot wound to the head by someone else who left the hospital. The man was pronounced dead. It is not clear where the shooting actually happened.

At 6:43 p.m. Sunday, two men – ages 54 and 66 – were in a vehicle in the 6100 block of South Bishop Street in Englewood when they heard gunshots and felt pain. The older man was shot in the head and was pronounced dead at the University of Chicago Medical Center, while the younger man was taken to the same hospital in good condition, police said.

Shortly after 11 p.m. Sunday, a 21-year-old man was walking on the sidewalk on the 600 block of North Sawyer Avenue in Humboldt Park, when someone in a grey sedan shot him in the chest. He was taken to Stroger Hospital, where he was pronounced dead.

About two hours later, a 31-year-old man and two other men were walking on the sidewalk on the 1400 block of East 73rd Street in the South Shore neighborhood, when someone in a black SUV started shooting. The 31-year-old man was shot in the left shoulder and armpit, and was taken to University of Chicago Medical Center, where he was pronounced dead.

A 21 year old male black was walking on the sidewalk when an occupant in a grey sedan fired shots.  The victim was taken to Stroger in critical condition with gsw’s to the chest. There is no one in custody and Area Four detectives are investigating.

In other shootings, an attack in the Chicago Lawn neighborhood left four people wounded around 3:30 a.m. Saturday. Police said the victims were standing next to a car on the 2400 block of West Lithuanian Plaza Court, when someone in a passing sedan opened fire, shooting each of them.

A 23-year-old woman was shot in the leg, and was taken to Holy Cross Hospital in good condition. A 29-year-old woman was shot in the arm, and was taken to Advocate Christ Medical Center in good condition. A 30-year-old man was shot in the leg, and took himself to Holy Cross, where he was in good condition. Another 30-year-old man was shot in the abdomen, and was taken to University of Chicago Medical Center in serious condition.

Two 14-year-old boys were wounded in a shooting at 3:45 p.m. Sunday in the 0-99 block of East 123rd Street in the West Pullman neighborhood. The boys were walking west on the block when a dark-colored vehicle approached them traveling east. Witnesses told police the shots came from the vehicle.

One of the boys was shot in the right thigh and was taken to the U of C’s Comer Children’s Hospital, while the other was shot in the left arm and was taken to the same hospital. Their conditions were stabilized, police said.

Meanwhile, a stabbing left a 5-year-old girl dead Saturday morning in the East Garfield Park neighborhood.

Police received multiple calls of a person stabbed in the 3200 block of West Fulton Boulevard around 9:15 a.m.

Police News Affairs Officer Jose Jara said firefighters were already treating the 5-year-old girl, Serenity Arrington, when officers arrived. She had been stabbed multiple times.

The officers were then approached by a woman who was placed in custody. The woman, Simone Austin, 27 — whom police said was Serenity’s mother — has since been charged with first-degree murder.

Serenity was taken to Stroger Hospital of Cook County, where she was pronounced dead, according to police and the Cook County Medical Examiner’s office. Neighbors said the woman taken into custody is the girl’s mother, but police would only say they believe the girl and the woman in custody are related.

At 12:14 a.m. Sunday, two people found a woman’s body in the North Branch of the Chicago River just west of the 3400 block of North Rockwell Street at 12:14 a.m. Sunday.

The woman had been stabbed to death, according to Chicago Police. She had a number of wounds to her face and neck.

The only details known about the victim are that she seems to be in her 20s and was wearing a black shirt and black jeans. Her death is now being treated as a homicide investigation.