CHICAGO (CBS) — At least 45 people were shot in Chicago this weekend, and nine of them had been killed.

The most recent fatal shooting happened around 2:50 a.m. Monday, when a 17-year-old boy was shot in the back as he was standing in an alley on the 6400 block of North Hamilton Avenue in West Ridge. Police said he was taken to St. Francis Hospital, where he was pronounced dead.

Around 2:15 a.m. Monday, a 24-year-old man and a 25-year-old man were sitting in a parked car on the 3400 block of West Carmen Avenue on the cusp of the North Park and Albany Park neighborhoods, when shots were fired. The younger man was shot in the back and the right hand, and was taken to Swedish Hospital in fair condition. The older man was shot in the head, and was pronounced dead at the scene.

At 1:40 a.m. Monday, a 29-year-old man was parking his car on the 3200 block of North Nagle Avenue in the Dunning neighborhood, when someone in a white sedan pulled up and shot him several times. He was taken to Advocate Illinois Masonic Medical Center, where he was pronounced dead.

This weekend’s shootings also included two mass shootings that happened within a period of an hour in different parts of the city’s South Side on Saturday.

At 5:38 p.m. Saturday, multiple people were in the 12200 block of South May Street when they heard shots and felt pain, police said. Witnesses said two black sedans came down the street and people inside started shooting at people who were standing on the sidewalk, on a porch, and inside a home, police said.

A 24-year-old man was shot in the right foot and a 29-year-old man was shot in the left torso and forearm. Both were taken to Advocate Christ Medical Center in Oak Lawn, where their conditions were stabilized police said.

A man about 50 years old was taken to the University of Chicago Medical Center after being shot in the right ankle. His condition was also stabilized, police said.

A fourth man of an unknown age was shot multiple times in the chest and was taken to Advocate Christ in critical condition, police said.

The cars from which the shots were fired fled north on May Street, police said.

About 38 minutes earlier, four people were also wounded in a separate shooting several miles to the north and west in Chicago Lawn.

Around 5 p.m. Saturday in the 6800 block of South Claremont Avenue, police said a 23-year-old man was shot in the lower back and a 39-year-old woman was shot in the right calf. Both were taken to the University of Chicago Medical Center, where their conditions were stabilized.

A man about 30 years old was taken to Advocate Christ Medical Center in critical condition with multiple shots to the abdomen, and a 38-year-old man was taken to the same hospital, where his condition was stabilized, after suffering a shot to the right ankle.

A witness said the assailant, a man standing 5 feet 6 inches to 5 feet 7 inches tall, fled east in the alley north of 69th Street.

There were also two shootings this weekend that left three people injured – one in Englewood on the South Side, the other in South Austin on the west.

At 4:04 a.m. Saturday, three people were in separate cars in the 7000 block of South Peoria Street when someone inside a passing vehicle opened fire and shot them all. Two men, both 27, suffered graze wounds – one in the arm and other in the back. The first man refused medical attention and was in good condition, the second was taken to the University of Chicago Medical Center in fair condition.

The third victim was a 49-year-old woman who was shot in the lower back side. She found her own way to Provident Hospital of Cook County, where she was in fair condition, police said.

Around 8:40 p.m. Saturday, three men were standing on the sidewalk in the 300 block of North Laramie Avenue when someone in a sedan fired shots. A 42-year-old man was shot in the left leg and was taken to Stroger Hospital of Cook County in good condition, while a 47-year-old man was shot in the left leg and left hand and was taken to Mount Sinai Hospital in good condition. A 33-year-old man was taken to the same hospital in good condition with a shot to the left leg.

In other fatal incidents, a 24-year-old man was found unresponsive on the ground at 5:38 p.m. Friday in the 8400 block of South Escanaba Avenue in South Chicago, with a gunshot wound to the side of his head. The man, identified as Isaiah Armstrong, was pronounced dead.

Another man was shot and killed around 10:05 p.m. Friday in the 5700 block of West Midway Park in the South Austin neighborhood.

Police said officers responded to a ShotSpotter alert of gunfire and found the man in the driver’s seat of a parked car, with multiple gunshot wounds to his face and chest. Based on a preliminary investigation, police believe a male suspect walked up to the car and fired multiple shots.

The victim was pronounced dead at the scene.

At 3:09 a.m. Sunday, a 39-year-old man was walking in the 7900 block of South South Chicago Avenue in the South Chicago neighborhood, when he was approached by another man who shot him in the neck. The victim was discovered unresponsive and was pronounced dead at the scene.

Just before 10 a.m. Sunday, a driver was talking to someone who was outside his vehicle in the 3900 block of West Roosevelt Road, when someone else came up and shot him inside his car.

The victim drove off after being shot, heading east on Roosevelt when he struck a parked vehicle that then struck a pedestrian waiting for a bus in the 3200 block of West Roosevelt Road. The pedestrian suffered minor injuries. The driver was taken to Mt. Sinai Hospital where he later died.

At 1:05 p.m. Sunday, a man was shot and killed in the 6900 block of South Campbell Avenue in the Chicago Lawn neighborhood. Police said the 26-year-old man was struck by unknown gunfire and was taken to Advocate Christ Medical Center in Oak Lawn, where he was pronounced dead.

In the 1300 block of South Avers Avenue in Lawndale, a man of an unknown age was found at 4:32 p.m. Sunday with gunshots to the head and chest. He was pronounced dead at Mount Sinai Hospital.

The Albany Park area, which has been in the headlines in recent weeks for an uptick in gun violence that has left residents alarmed, saw two shootings in which the victims survived this weekend in addition to the fatal shooting early Monday on Carmen Avenue. There was also a shooting this weekend just to the south and west in Old Irving Park.

In the 4100 block of West Lawrence Avenue in the Mayfair community – part of the Albany Park police district and community area – an 18-year-old man was shot in the chest and back around 6:45 p.m. Friday. He was taken to Advocate Illinois Masonic Medical Center in an unknown condition.

Around 10:16 p.m. Friday, a 38-year-old man was found with gunshots to the head, chest, and arm in the driver’s seat of a vehicle in the 2700 block of West Agatite Avenue, in the Ravenswood Manor community on the eastern edge of Albany Park. He was also taken to Advocate Illinois Masonic, where he was in serious condition.

At 12:41 p.m. Sunday, a 19-year-old man was shot in the arm in the 4700 block of West Irving Park Road in the Old Irving Park neighborhood. He was taken to Community First Medical Center in good condition.

Over a period of three consecutive days last week, seven people were shot in Albany Park and two of them were killed. The CPD has pointed to gang feuds as the reason for the increase in shootings.