A swimming instructor described how she pulled a schoolboy from the bottom of an Oxfordshire pool on the day he died.

Sara Allen, a swimming teacher at Lord Williams's School in Thame, told an inquest into the death of Nathan Matthews: "It was the most traumatic experience of my life."

Nathan, 11, a pupil at Stokenchurch Primary School, died at Oxford's John Radcliffe Hospital on July 12, 2004, after being pulled from the bottom of the pool at Thame Leisure Centre during a school fun day.

Miss Allen told the jury at Oxford Coroners Court today: "My initial thought was that he had got out - until I got to the corner and I couldn't see him."

She added: "One of the children said: Miss...Nathan didn't come up'.

"I blew my whistle and shouted get help, I'm going in'.

"I completely submerged. I paused before to take a breath. I picked him facing me and put him in my arms and carried him to the side."

With the assistance of lifeguard Rob McGill, Nathan was put in the recovery position, but Miss Allen was unable to check his airway because his jaw was clenched, the inquest heard.

Previous evidence revealed inconsistencies as to how many lifeguards were on duty, whether Nathan was put in the correct recovery position, when he stopped breathing and when CPR began.

The inquest continues.