About 30 people were on a deck when it collapsed on Thursday evening at a home in O'Fallon, according to police.
Six people were injured, with the most severe injuries being broken bones, at 1330 Winding Creek Court, according to a news release by O'Fallon Police Capt. James Cavins.
On Friday morning, Cavins said there would not be a police investigation.
"It's just a tragic accident," he said.
Cavins said the city's code enforcement officers would be looking at the deck "from a structural standpoint."
Ted Shekell, the community development director, was not immediately available for comment about the deck's permit history or inspection on Friday morning.