UPDATE: More than 50 people shot over Fourth of July weekend.

A surge of overnight violence struck Chicago on the Fourth of July with at least 22 people shot overnight, bringing the total number of people shot since the long holiday weekend began to 37.

The holiday’s latest homicide involved a young man who was killed late Friday night after being shot by police officers in the Portage Park neighborhood.

Police said officers approached the man just before 10 p.m. in the 3800 block of North Cicero Avenue when they saw “an object protruding from his waistband” and tried to stop him. The man fled the scene and pointed a “large revolver” at pursuing officers, according to a statement from Chicago police.

“He takes his left hand and pulls something out from under his arm, put it in his right hand and starts to turn,” said Fraternal Order of Police spokesman Pat Camden. “He’s got a .44 magnum with a 8- to 10-inch barrel.”

Police then fired shots, fatally striking the man.

According to the Cook County Medical Examiner’s office, the man is believed to be in his late teens or early 20s.

The shooting marked the third police-involved shooting in 18 hours.

At least two others have been killed in shootings since Thursday.

The first homicide took place shortly after 4 p.m. Thursday in the 3800 block of West Monroe Street when two women were shot in the East Garfield Park neighborhood on the city’s West Side.

One woman, 21, was shot in the head and pronounced dead at the scene, police said. The second person, also 21, was shot in the arm, police said.

On Friday, a man was killed and another man was wounded in a shooting at a strip mall at 63rd Street and Damen Avenue.

Police said the men were standing outside a building when a black vehicle pulled up and someone inside the vehicle opened fire, striking both men.

A 34-year-old man was taken to Holy Cross Hospital and later pronounced dead. A 35-year-old man was taken to John H. Stroger Jr. Hospital of Cook County in critical condition, according to Chicago Police News Affairs Officer Janel Sedevic.

Area South detectives are investigating the shooting, police said.

At least 21 others were wounded in Fourth of July shootings Friday night through early Saturday morning.

Just before 10:30 a.m., a 33-year-old man was shot in the leg and abdomen in the 8700 block of South Houston Avenue, police said. The man was taken to Northwestern Memorial Hospital in serious condition.

A 26-year-old man was shot in the buttocks in the 9600 block of South Avenue L around 5:20 a.m. Saturday. He was taken to Trinity Hospital in good condition, according to police.

Around 5 a.m., a 33-year-old man was shot in the 5200 block of W. Washington Boulevard. The man, who police said was highly intoxicated and uncooperative, was shot in the right leg and taken to John H. Stroger Jr. Hospital of Cook County in good condition. Police were still attempting to located the crime scene Saturday morning.

A 33-year-old man was shot in the city’s Austin neighborhood around 3 a.m. The man was listed in guarded condition at Stroger Hospital with wounds to the back and neck after being shot in the 700 block of North Lavergne Avenue, according to authorities. Police say he was involved in a verbal altercation with a group of people in a van. During the argument, the people exited the van and one person punched the victim before another fired shots at him. The offenders then fled northbound on Lavergne Avenue.

About two hours earlier, a 35-year-old man suffered multiple gunshot wounds to the body in an apparent drive-by shooting in the 2800 block of South Homan Avenue, police said. The man was taken to Mount Sinai Hospital in critical condition.

In another possible drive-by shooting, a 31-year-old man was shot in the shoulder around 1:10 a.m. in the 1800 block of South Allport Avenue in the Pilsen neighborhood. The man transported himself to Stroger Hospital in good condition.

Two people were shot just before 1 a.m. in the city’s Englewood. Two suburban teens were driving near 58th and Laflin streets when gang members opened fire on their car, according to Chicago Police News Affairs Officer Janel Sedevic. A 16-year-old boy was shot in the shoulder and taken to Advocate Christ Medical Center in good condition and a 17-year-old suffered a graze wound to the arm and was taken to Saint Bernard Hospital and Healthcare Center in good condition. Police believe the teens were mistaken for rival gang members. Area South detectives are investigating.

Around the same time, a 30-year-old man was shot in the parking lot of a Walgreen’s at 63rd Street and Austin Avenue. Police said the man was standing in the parking lot when someone approached him and opened fire. The victim is a documented gang member, police said.

Around 12:30 a.m., a 17-year-old boy was shot in the ankle after someone fired shots from a passing vehicle. The teen was taken to Mount Sinai Hospital in good condition, police said.

At about 11:40 p.m. a 26-year-old man was shot while celebrating with relatives in the 7600 block of South Oglesby Avenue. Police said the man was in the front of a residence talking with relatives when two offenders wearing dark-colored hoodies walked up and began firing handguns. The victim was struck in the right arm and torso and taken to South Shore Hospital in stable condition.

Twenty minutes earlier, a 26-year-old man was shot twice in the leg in the 5100 block of West Wabansia Avenue in the North Austin neighborhood. He was taken to Mount Sinai Hospital in good condition.

Just before 11 p.m., two people were shot during an argument in the 11700 block of South Union Avenue. Police said a 23-year-old woman was driving with her brother when she got into an argument with a 22-year-old man in another vehicle. The 22-year-old man fired at the woman, striking her in the arm and her brother then shot the man two times in the torso. Both the woman and man were transported to Advocate Christ Medical Center in stable condition. Charges are pending against the brother and the 22-year-old offender, police said.

Around the same time, three people were shot at a party in the Altgeld Gardens neighborhood. Police said a large party was being held in the area when shots were fired into the crowd. A 24-year-old man was taken to Advocate Christ Medical Center with a wound to the buttocks along with a 26-year-old man who was shot in the head. Another 24-year-old man was shot in the back and taken by someone at the scene to Roseland Community Hospital but he was later transferred to Advocate Christ Medical Center, police said. All three were listed in stable condition.

Around 10:30 p.m. a 34-year-old woman was shot near 71st Street and Carpenter Avenue after she told police four or five men fired a gun in her direction. She was taken to Advocate Christ Medical Center with a wound to the leg and was listed in good condition.

Just before 10 p.m., a 26-year-old man shot himself in the leg in the 700 block of North Christiana Avenue in the East Garfield Park neighborhood. The man was taken to Stroger Hospital in good condition.

Around 9:15 p.m., a 40-year-old man was wounded by a falling bullet while drinking with friends in the 5000 block of North Kildare Avenue. The man was treated and released from a nearby hospital.

An 18-year-old man was shot in the stomach at about 6:35 p.m. in the 6700 block of South Wolcott Avenue, police said. He was taken to Stroger Hospital in serious condition. Details surrounding the shooting were not immediately available.

At least 11 other people have been shot since Thursday afternoon.