Four people wounded in one incident were among 13 people shot Tuesday across Chicago.

The mass shooting happened about 8:25 p.m. in the Humboldt Park neighborhood on the West Side. The four people were on the porch of a home in the 800 block of North Monticello when someone came up to them and opened fire, Chicago Police said.

A 17-year-old boy suffered a gunshot wound to the left side and a 66-year-old man was shot in the upper right side, police said. They were both taken to Mount Sinai Hospital.

A 28-year-old man was shot in the abdomen, while a 31-year-old man was also shot in the left side, police said. They were taken to Stroger Hospital. All four victims’ conditions were stabilized.

The day’s latest shooting left a 15-year-old boy wounded in the East Chatham neighborhood on the South Side. About 9:15 p.m., he was walking west on 82nd Street at Ellis Avenue when several males walked up to him, one of whom pulled out a gun and fired shots, police said. The boy was shot in the left arm and suffered a graze wound to his abdomen. He was taken to a Christ Medical Center in Oak Lawn in good condition.

A 31-year-old woman was shot about 7 p.m. in the Logan Square neighborhood on the Northwest Side. She was driving a vehicle in the 2100 block of North Central Park Avenue when someone on foot fired shots and she was struck in the left thigh, police said. She was taken to Illinois Masonic Medical Center, where her condition was stabilized. She was not believed to be the intended target of the shooting.

About 6:25 p.m., a 21-year-old man heard gunshots and realized he was shot in the thumb in the 7000 block of South Paulina in the West Englewood neighborhood on the South Side, police said. He was taken in good condition to Holy Cross Hospital.

Two people were wounded in a South Shore neighborhood shooting about 3:50 p.m. on the South Side. Someone got out of a dark-colored vehicle in the 6800 block of South Stoney Island and fired shots, police said. A 26-year-old man was taken to Stroger Hospital with a gunshot wound to the buttocks. A 28-year-old woman was shot in the groin and taken to Northwestern Memorial Hospital. Both were listed in good condition.

About 12:50 p.m., a 16-year-old boy was shot in the chest in the 7800 block of South Dobson near a Greater Grand Crossing neighborhood high school on the South Side. He was taken in critical condition to Christ Medical Center. The shooting happened near Hirsch High School, 7740 S. Ingleside Ave. The circumstances of the shooting weren’t immediately available.

Ten hours earlier, two men were shot in another South Shore attack. The men, ages 20 and 31, were walking at 2:48 a.m. in the 7500 block of South South Shore when another male pulled out a gun and fired shots at them, striking the younger man in the back and the older man in the leg, police said. Both men were taken to Northwestern Memorial Hospital, where the younger man was listed in critical condition and the older man’s condition was stabilized.

The day’s first shooting happened about 12:15 a.m. in the West Garfield Park neighborhood on the West Side. A 33-year-old man was driving east in the 4400 block of West Jackson when he heard gunfire and realized he’d been shot in the groin, police said. The origin of the shots was not known. The man was taken to Stroger Hospital, where his condition was stabilized.

More than 2,180 people have been shot so far in 2017, 378 fatally, according to data maintained by the Chicago Sun-Times.

On Monday, two men were killed and at least nine other people were wounded in shootings Monday across the city.