The overnight shooting occurred in a building where a party was being held downtown shortly after 1 a.m. Central Time.
Mayor Tishaura Jones said that a 17-year-old teen died in the shooting.
According to CNN, police Chief Robert Tracy stated at a news conference on Sunday that a 17-year-old suspect is currently in custody.
Jones stated, "Families across the St. Louis region woke this Father's Day to the news of yet another mass shooting."
Jones stated, "It's every parent's worst nightmare, tenfold." My thoughts and prayers are with all of the grieving families today. "The gun violence that tore into their lives will leave physical and mental scars for all those attending," Jines added.
The chief stated that the ages of the injured victims range from 15 to 19 years old. He also said that a 17-year-old girl was trampled as she fled the scene and suffered serious spinal injuries.
Tracy stated that numerous firearms, including an AR-15-style rifle and a handgun, were retrieved by police from the scene.
The office building's owner and the party's organizer are the subjects of an investigation by the police.
According to CNN, Mayor Jones expressed fear and sadness at the loss of the once-safe location in light of the increasing number of mass shootings occurring across the United States.
Mayor Jones stated during the news conference, "There were places to go and things to do, and we were safe." No longer so much."
Where can our infants, whose families are struggling to make ends meet, go to have fun and see their friends? She went on.
St. Louis authorities are attempting to make more places of refuge for youngsters to get them far from hazardous regions, similar to where Sunday's party was held, by utilizing assets to make interests in youth programs, Jones said, revealed CNN.
In the United States, the issue of mass shootings is becoming an increasingly concerning one.
Joe Biden, the US President, had called for stricter gun laws on multiple occasions. In February, Biden stated that, in light of the rise in mass shootings, it was high time to reinstate the ban on assault weapons and that the country required additional resources to reduce gun crime.
"10 years ago the ban was law, mass shootings went down," Joe Biden stated in his first major speech to a divided Congress after Republicans took control of the House of Representatives. Mass shootings tripled after Republicans let it expire. Let's complete the task and ban assault weapons once more."