A father whose son died in police custody has vowed he will never give up his fight for the truth.

Neil Juwaheer, 35, was holidaying in Fortaleza in north-east Brazil, when he was arrested for burglarly after scaling a wall.

He later died in police custody in circumstances which remain unclear.

At his inquest this afternoon an open verdict was reached at South London Coroners Court.

Following his death a post mortem found him to have died of a drug overdose, claiming he had swallowed a packet of cocaine.

But after flying out to see his body, Neil’s parents Joe and Pauline arranged for another doctor to examine his body.

Dr George Samuel Sanguinetti Fellows found he had a blood clot caused by a head injury, and various skin abrasions all over his body.

Mr and Mrs Juwaheer are certain their son, a former estate agent who lived in Carshalton Beeches, was beaten to death by the Brazilian officers when he died on July 8 2007.

In a police report read out by Coroner Selena Lynch, it was confirmed that antenna wire had been tied around their son’s hands and feet to restrain him.

Neil was arrested after climbing over a wall into a condominium.

The police report stated he was foaming at the mouth when they took him in and appeared highly agitated at the station.

The court heard he later collapsed on the floor, and officers thought he was having an epileptic fit or heart attack.

A toxicology report following his death found him to have 100,000mg of cocaine in his blood, enough to cause delirium and delusions.

The post mortem also reported a small packet containing traces of cocaine was found in his stomach.

In their seven-year pursuit of the truth, Mr and Mrs Juwaheer have pushed for DNA tests to be carried out on the packet.

But for 18 months authorities in Brazil claimed it was missing.

A packet has now surfaced, but delays in judicial proceedings mean DNA testing has still not been carried out.

Joe said: "The bag was produced after (his death.) It was planted there.

"He had an injury to his head, and also had injuries to his toes and other parts of his body.

"He was tied up and I believe tortured.

"If he was found foaming at the mouth and in this terrible mess, why was he taken to the police station and not the hospital?

"We will never give up trying to find out how our son died."

Dr Sanguinetti Fellows found no evidence their son’s death was due to cocaine poisoning.

In an email he sent to Joe, who runs Croydon care home Thornton Lodge, stating his findings, he said: "There was violence direct, intentional and repeated by instrument repeatedly, whose most serious consequence in the context of multiple trauma was head trauma."

In court this afternoon the coroner described the cause of Neil’s death as unascertained.

The unanswered questions and the fact no witnesses could be called in from Brazil, are what lead Coroner Selena Lynch to come to an open verdict.

She said: ""There are so many questions we would want to speak to the witnesses about.

"Sadly that is not possible.

"I can’t give a cause of death here because I really don’t know.

"An open verdict is all I can record, I know that doesn’t help you as a family."