Updated 1/24/11 9:03 p.m.

JOLIET, Ill. (CBS/STMW) – Questions remain Monday morning after a 2-year-old boy was severely injured when he fell down an elevator shaft at a Joliet hotel.

On Sunday, the boy fell from the second floor to the basement at the Plaza Hotel, at 26 W. Clinton St. in Joliet.

The boy, a sibling and their mother were in a room when the 2-year-old slipped away unnoticed, went to an elevator and began playing with the buttons.

LISTEN: Newsradio 780’s Bernie Tafoya reports

Police say the elevator began to move and the toddler pushed the “stop” button, but when he did, there was about a 16-inch space between the elevator and the wall.

The child fell about 30 feet. He was initially taken to Silver Cross Hospital in Joliet, and was later reported in critical condition at Children’s Memorial Hospital in critical condition.

Hotel Guest Karl Posey said she could hear the child screaming as he plunged down the shaft, “He was in the elevator. Because we heard him right there in the elevator. So I went to get my screwdriver to try to pry the door open. By the time I got back, he done fell.”

Police say surveillance video shows it just took seconds for the child to wander outside his mothers room and into some serious trouble.

“He actually walks through the hallway and to the elevator. He presses the elevator button, enters the elevator and on the video, you can actually see the little boy pressing the buttons,” said Joliet police Chief Fred Hayes.

The city of Joliet says a contractor inspected the elevator in October and that it passed inspection.

Firefighters say this incident was an unfortunate accident for a mom whose attention turned away from her child, “It only just takes a few minutes. And clearly in this case it was just within 5 minutes. The boy walked out of that room and the mother then came looking for the boy.”

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