LONDON - The son of world motorsport chief Max Mosley died of an accidental cocaine overdose, a British coroner ruled Wednesday. Alexander Mosley, 39, was found slumped at his desk by his cleaner in his home in Notting Hill in west London on May 5.

Westminster Coroner's Court heard that Mosley was a long-term heroin user who suffered from depression. He had sought help but habitually returned to drug-taking, doctors said.

He died surrounded by crack pipes, needles and other drug-taking paraphernalia.

Doctors found traces of ketamine, MDMA (ecstasy) and heroin or morphine, as well as large traces of the by-product of cocaine, in his urine. Coroner Dr Paul Knapman recorded a verdict of death by non-dependent drug abuse.

"This is a tragedy for a man who, in so many respects, had so much potential. Unfortunately his propensity to return to taking drugs has caused his death at the age of only 39," Knapman said.