An inquest jury has ruled there was adequate supervision during the school swimming lesson where Nathan Matthews drowned.

Nathan, 11, died after getting into trouble in the water during a relay race at Thame Leisure Centre.

A swimming instructor pulled him from the pool and lifeguards tried to revive him on July 12, 2004. He was declared dead at the John Radcliffe Hospital in Oxford.

After a nine-day hearing at Oxford Coroner's Court, a jury of six men and three women decided that the cause of death was drowning.

Returning a narrative verdict, the jury foreman said that the Stokenchurch Primary School pupil was taking part in "adequately supervised swimming activities" and during an organised race "for reasons that cannot be ascertained" he went under the water.

She said: "Based on the evidence, despite all reasonable efforts to revive Nathan Matthews, attempts were unsuccessful.

"After considering the expert medical evidence and on the balance of probabilities, we are unable to identify the primary event that led to the death."