CHICAGO (CBS) — Chicago Police have deployed 81 new probationary officers onto the streets to help fight violence in the city. The new officers are joining the ranks as the department is responding to another weekend that saw dozens of people shot across the city.

Police Supt. David Brown said the new recruits started on Sunday, and are being deployed to districts across the city, including the 2nd District on the South Side. They were already patrolling the streets and getting to know the people on their beats. They are the first class of new officers who participated in youth-led neighborhood tours during their training.

“Residents here in the 2nd District and throughout the city look forward to additional investments in community safety. I definitely know the rest of the 13,000 cops are looking forward to the additional support,” Brown said.

The additional officers are hitting the streets as the department prepares again to cancel days off for officers and move them to 12-hour shifts over the next two weekends.

In a memo obtained by CBS 2 Political Investigator Dana Kozlov, police said they are canceling days off for officers on the day and evening watch on Saturday, Aug. 29, and the overnight watch into Sunday, Aug. 30, and placing officers on longer shifts for those times.

The reason was “multiple large gatherings” planned for that day, the memo said.

At least 64 people had been shot in Chicago this weekend, and four of them had been killed, between Friday evening and Monday morning.

In the earliest fatal incident, two people were also wounded.

At 12:13 a.m. Saturday, three people were standing outside in the 800 block of North Lorel Avenue in the South Austin neighborhood when a man got out of a black Jeep Cherokee and fired shots, striking them each, police said.

A 26-year-old man was shot in the neck, chest, and leg and was pronounced dead at Mount Sinai Hospital. A 37-year-old man and a 42-year-old woman were each shot in the leg and were taken to Stroger Hospital of Cook County in fair condition.

The man who was killed was identified as Ronald J. Boyd.

At 2:04 a.m. Saturday, two men were on the porch of a house in the 8500 block of South Burley Avenue in the South Chicago neighborhood when a man exited a vehicle and fired shots, striking them both. A 33-year-old man was shot in the head and abdomen and was pronounced dead at the scene, while a 32-year-old man was shot in the abdomen and leg and was taken to the University of Chicago Medical Center in critical condition.

The man who was killed was identified as Antoine L. Rose.

At 5 a.m. Saturday, a unidentified man was unresponsive with a gunshot wound to the head in the 100 block of North Mayfield Avenue in the South Austin neighborhood. He was taken to Loyola University Medical Center, where he was pronounced dead.

At 6:20 a.m. Sunday, a 27-year-old man was shot multiple times in the chest and pelvis in the 1800 block of South Komensky Avenue in Lawndale, after a quarrel with someone he knew. The man was pronounced dead at Mount Sinai Hospital.

A shooting wounded three people in the 1100 block of South Albany Avenue in Lawndale at 2:53 a.m. Saturday. Police said a 37-year-old woman was found outside with a gunshot wound to the leg and was taken to Mount Sinai Hospital in critical condition. Police later learned a 20-year-old man was shot in the arm and leg and was taken to the same hospital in good condition, while a 32-year-old man was shot in the foot and was in good condition at Stroger.

Also in Lawndale, three men were shot around 5 a.m. Sunday in the 2900 block of West Fillmore Street. Someone fired at the men from a gray sedan, and they were all taken to Mount Sinai in fair condition. A 42-year-old man was shot in the back, a 26-year-old man was shot in the left biceps, and a 24-year-old man was shot in the hip and buttocks, police said.

At 4:34 a.m. Sunday, three people were shot in the 1000 block of West 14th Street on the Near West Side. A 23-year-old woman was taken to Stroger in fair condition with shots to the chest and abdomen, a 29-year-old man was taken to the same hospital in fair condition with a shot to the left arm, and a 33-year-old man was taken to Stroger in critical condition with a gunshot wound to the head.

Four men were wounded by gunfire around 4:30 p.m. Sunday in the 6600 block of South Halsted Street in Englewood. The men were out in front of the business when a vehicle pulled up and someone fired shots.

A 23-year-old man suffered a graze wound to the arm and was taken to St. Bernard Hospital in good condition. A 24-year-old man was grazed in the back and buttocks and refused treatment. A 27-year-old man was shot in the calf and knee and was also taken to St. Bernard in good condition. A 28-year-old man suffered an injury to the hand and was uncooperative at the scene, and his condition was not known, police said.

Around 7:30 p.m. Sunday, a man and woman were shot in the 2500 block of West Adams Street on the Near West Side. The 22-year-old man was struck in the back and walked into Stroger Hospital of Cook County, where he was in critical condition. The woman was struck in the head and was also in critical condition, police said.