The mother of a Jewish student who died after fleeing an extremist group in Germany has vowed to fight on for a full investigation into the circumstances of his death.

Erica Duggan has conducted a 12-year campaign to find out what happened to her son Jeremiah.

Following an inquest in London last week that "totally rejected" a previous ruling by a German court that he had committed suicide, she said: "I will not stop until the German authorities recognise this UK verdict and look into his death."

Jeremiah Duggan was killed after being hit by a car in Wiesbaden in 2003.

Giving his verdict, coroner Andrew Walker said that the fact that Mr Duggan had revealed himself to be Jewish while attending a conference held by the far-right LaRouche organisation may have had a bearing on how he died, causing him to be at risk from other members of the organisation.

Mr Walker also rejected the assertions of expert witnesses instructed by the Duggan family that the scene of Jeremiah's death had been arranged to appear as suicide.

Speaking at her home in north London this week, Mrs Duggan said that the coroner's ruling had left her disappointed.

"The result is bitter-sweet because there are still so many unanswered questions," she said. "If the coroner could see Jeremiah's death was potentially related to him being Jewish and caught up in this horrible group, then surely we need to investigate the group?"

She added that the 12-year struggle to establish how Jeremiah had died had taken its toll.

"I lost a son that day but I also lost a part of my life. It has totally consumed me. It is me who has done all that work. It is wrong that a mother has to investigate her own son's death. I've yet to see how the law has served me.

"I've worked day and night for answers. But I can never give up trying to understand what happened to him. It has taken us 12 years and we still only have half an answer."

Mrs Duggan has instructed her lawyers to request the authorities in Germany to reopen the investigation, and called on the British embassy in Berlin to support her. "It seems the Germans are closing their minds to the threat the LaRouche organisation poses," she said.

The LaRouche movement, which was set up in the 1960s, is centred around controversial American political figure Lyndon LaRouche. It has been accused of promoting antisemitic conspiracy theories.