A six-year-old boy who was found facedown in a swimming pool in Busan during a 3:1 lesson died Wednesday afternoon, the Busan police said Thursday. The boy had been in critical condition for a week since the accident.

The child was found unconscious near a pool ladder at around 7:45 p.m. on Feb. 8, and it was determined that he drowned after his life jacket became stuck between the ladder’s rungs while he was diving into the water.

Surveillance camera footage shows the swimming instructor tending to a pupil at the other end of the pool, while the victim and another child were on the opposite end.

The pool, owned and operated by an apartment complex where the deceased lived, is about 1.4 meters deep, slightly deeper than the child's height of 1.09 meters. There was no lifeguard on duty at the time of the accident, police said.

"My child died because of the carelessness of the safety personnel at the pool. This is something that should not have happened and could have been prevented," the child's mother said during an interview with local media.

Police are investigating the exact cause of the accident, while considering negligent homicide charges for the instructor and pool officials.