A tragedy happened in suburban Chicago. A medical helicopter that was carrying an infant patient crashed and burned killing all four passengers. It seems the air craft clipped a radio tower and crashed into a wooded area near the Windy City.

Investigators are currently trying to find out whether the lights on top of the radio tower were on. This was the sixth deadly crash which involved a medical helicopter this year. The last similar crash took place in Maryland and four people died in it as well.

The helicopter was transporting 1-year-old Kirstian Blockinger of Leland to the Children's Memorial Hospital in Chicago from Valley West Hospital in Sandwich. The helicopter crashed into the Night Heron Marsh Forest Preserve on Eola road just north of Liberty Street. The fuselage was burning when local firefighters arrived at the scene.

"The impact was tremendous. The debris is scattered over that area that I explained is 75 to 100 feet," said Aurora Assistant Fire Chief John Lehman, "and so there really is no aircraft left."

The helicopter was operated by emergency medical transport company Air Angels Inc.

The crash occurred a few minutes before midnight Wednesday. A snapped wire was hanging from the 734-foot radio tower when investigators got there. The helicopter was flying about 50 feet below the top of the tower and investigators are trying to establish if the tower’s lights were on and what happened exactly.

"I can say that when I was out here last night after the accident that the lights on the tower were not lit," said John Brannen with the National Transportation Safety Board on Thursday.

The 1-year-old baby girl was being carried to the Children's Memorial Hospital because a closer hospital had no room for her there. The little girl had suffered epileptic seizures.