A 12-year-old Florida boy died while swimming in a hotel pool in Fairview Heights, Illinois, Tuesday.

Police said the boy was swimming with an older sister and younger brother when he decided to see how long he could hold his breath under water. While his sister tended to his brother, he was under water for several minutes until he was able to be pulled from the water by a family member.

The boy was given CPR by officers and his father until an ambulance could arrive. He was rushed to the hospital, where he was pronounced dead.

Police said they do not know why he could not resurface, because he was described as a good swimmer by his family.

Police have scheduled an autopsy for Wednesday, but suspect the death to be an accident.