An inquest has heard how a 14-year-old boy drowned after going to the aid of two friends in a tributary of the River Thames.

Baltazar Da Costa, who was born in Timor-Leste and lived in Stanford in the Vale in Oxfordshire, was among at least 11 people who died in water-related incidents during the heatwave across the country at the end of May.

Thames Valley Police was called to the river near Donnington Bridge at about 17:30 BST on 27 May.

The inquest at Oxford Coroner's Court heard that Baltazar, who could not swim, died at the scene.

He had been with a group of friends playing with a ball in the river when it landed in deeper water, the court heard.

Two girls who went to try and retrieve it got into difficulty and when the youngster went to help he slipped beneath the river.

Jaydan Lockyer, who had been sitting on the riverbank with his girlfriend, said in a written statement that he jumped in and was able to bring part of the group to safety.

"One of the girls told me there was one more," he said.

"I looked around and couldn't see anyone else in the water. It was very dark and visibility was extremely poor."

He described himself as a "strong swimmer" but was shocked at how quickly he became tired, feeling like he had "weights" on his feet.

His girlfriend Sabrine Houali said they had seen children splashing around, but at 17:00 heard shouting and screaming and "realised the situation was serious".

"I saw one remaining child come briefly to the surface before they disappeared under the water again," she said.

Baltazar, who was seen wearing a buoyancy aid on the day, was found under the water shortly after 18:00.

Paramedics worked for more than an hour to try to resuscitate him, but he was pronounced dead at the scene.

In the days after his death, people gathered to light candles in memory of the teenager.

Coroner Darren Salter recorded a finding of accidental death.

He told Baltazar's parents: "I know there's little I can say that will offer any comfort, but I'd like to offer my condolences, and I know you have the support of wider family and the wider community, and I hope this will help at this sad and difficult time."

Previously, the area near Donnington Bridge was the focus of a water safety campaign by Oxfordshire Fire & Rescue Service and The Royal Life Saving Society.

In 2012, 15-year-old Mohammed Hussain died after jumping from the bridge into the river.

Aown Dogar, 13, drowned at the site in 2015 after playing in waist-deep water and being taken out of his depth by a ledge in the river.