A father and his 22-year-old son were killed when their small plane apparently flew into a developing storm on their way home from a St. Louis Cardinals game, with investigators saying the aircraft appeared to make a last-minute turn before spiraling down into a rural Illinois tree line.

The pilot, 48, and his son took off from St. Louis Regional Airport in Bethalto late Thursday and were headed to Siloam Springs Municipal Airport in Arkansas when the plane crashed near Waterloo, Illinois, the Monroe County Sheriff's Department in Illinois said in a press release.

The father and son have been identified as Jimmy Don Lewis and Brayden Ty Lewis, the Monroe County Coroner’s Office confirmed to avoid the inclement weather, before entering what appeared to be a descending spiral. Radar contact was subsequently lost."

Emergency crews were dispatched around 2:34 a.m. Friday after reports of a possible aircraft crash south of Waterloo. Search efforts were hampered for hours by low clouds, rain and poor visibility, forcing authorities to rely on a massive multi-agency response that included specialized drone teams from Illinois and the St. Louis region.

An ARCH Air Medical helicopter eventually located the wreckage at about 7:40 a.m. in a tree line near the Columbia Quarry after investigators narrowed the search area.

"We extend our deepest condolences to the victims’ family and loved ones," authorities said after confirming both occupants of the aircraft had died in the crash. "Our thoughts and prayers remain with them during this incredibly difficult time."

Kelsey Lewis told the Federal Aviation Administration later assumed responsibility for the crash scene, while the National Transportation Safety Board and the FAA continue to investigate the cause of the crash.

Officials emphasized that the findings released so far are preliminary and that the federal investigation remains ongoing.