Complex sentence: The resulting fight over the balloons would injure 20 attendees; following the incident, LG announced that it would pay the hospital bills for anyone injured in the event, and called off plans to hold similar events in other South Korean cities.
Split into simpler sentences: The resulting fight that broke out over the balloons would injure 20 attendees; following the incident, LG apologized and stated that it would pay for the medical treatment of those injured in the event. LG also called off plans to hold similar events in other South Korean cities.