A 13-year-old boy was among five people killed in unrelated shootings across Chicago over the weekend, which also left 20 others injured, according to police.

The violent weekend in the nation's third largest city erupted despite a 20% drop in shootings in Chicago through the end of summer, according to Chicago police crime statistics. Homicides have also plummeted 16% from last year, according to the statistics.

Despite recent efforts by police to curb shootings, at least 25 people were shot in Chicago between Friday evening and Sunday afternoon, according to a review of weekend crime incidents by ABC News.

Last weekend, 30 people were shot, two fatally, in gun violence across the Chicago, police said.

Boy sitting on park bench killed

The youngest victim shot to death over the weekend was identified as 13-year-old Lavel Winslow, according to the Cook County Medical Examiner's Office. The boy was fatally shot while attending a friend's birthday party at Lerner Park on the city's North Side.

The shooting unfolded around 10 p.m. Friday, according to police.

"Witnesses heard loud pops followed by multiple people fleeing the area on foot," police said in an incident report.

Winslow was found sitting on a park bench with a bullet wound to the head, according to police. He was taken to St. Francis Hospital in Chicago, where he was pronounced dead.