French investigators believe a teenager who was found dead in the River Seine may have killed himself because of an unsuccessful job interview, an inquest heard.

The body of Charles-Joseph Coupe, 19, of Churchside, Vigo, was discovered in the water five days after he disappeared from his home in a village near Paris.

French authorities told his mother, Eve Diakhate, and her partner, Bob Fitton, the former St John’s Catholic Comprehensive School pupil took his own life.

However, the family believe he may have been murdered.

The tragedy was the first of two to hit the family in five months.

Charles-Joseph died in September 2014, then, in February this year, Bob’s 18-year-old son Joe was killed in a crash in Vigo along with his friend, Charlie Carver.

A post mortem in France ruled Charles-Joseph died from drowning but a second report ordered in the UK was unable to determine the cause of death because of his body’s condition.

Unhappy at the investigation, relatives contacted Kent Police, Gravesham MP Adam Holloway and French president Francois Hollande to press authorities after it was revealed several organs were missing during the post mortem.

At the inquest on Tuesday, a report by French investigators revealed tests had proved Charles-Joseph was alive when he entered the water.

However, third-party involvement was ruled out, with prosecutors believing Charles-Joseph killed himself.

Investigators said he attended an unsuccessful job interview two days before his disappearance, which jeopardised his career plans, and that CCTV footage from a fast food restaurant showed he had removed his own clothes.

Coroner Roger Hatch explained that, although he had powers through the Foreign and Commonwealth Office to receive information from French police, he was unable to summon investigators to the inquiry for questioning.

He recorded an open verdict.

Speaking after the inquest at Gravesend Old Town Hall, his mother Eve refused to believe the police’s version of events, producing a letter from a friend who said he could not believe Charles-Joseph would have taken his own life.

She said: "Everything that they have to show he was suicidal, we have conclusive proof to show he wasn’t.

"He always intended to come back to England. It would be impossible that he would do that. I don’t believe in the French police and I will never know what happened to my son.

"We are still in touch with our solicitors but I just put my faith and love in God. I’m waiting for him."

The family also disputed the explanation that an unsuccessful interview may have played a part in his death, insisting the job he applied for was at McDonald’s.

Charles-Joseph returned to his native France to start a business course and dreamed of moving to Los Angeles to start his own company.

Friends and relatives described him as “full of life”.

His body was buried at St Mary The Virgin Church in Stansted, where he now lies close to Joe.

Catch up with all the latest video news on our KMTV bulletin