The grieving mother of a teenager killed with his girlfriend in a "three-on-a-bike" horror crash today called on police to reinvestigate the accident.

Anthony Bentley, 18, and 15-year-old Natalie Athey, died instantly when they were hurled from the 125cc trials bike as it was being driven by Anthony in Hunsworth Lane, Hunsworth, Cleckheaton, in January.

A second passenger, Daniel Booth, 14, survived the crash.

Coroner Rogher Whittaker last week ruled that Natalie was unlawfully killed and Anthony died accidentally. Mr Whittaker said Natalie's death resulted from a breach of duty of care to her by her boyfriend which was criminal.

The inquest heard the tyres of the bike, which belonged to a friend of Anthony, were under-inflated, a footrest was missing and Natalie and Daniel were not wearing helmets. Anthony was driving above the 30mph speed limit.

Anthony's mother, Denise Fox, said she believed there were aspects of the accident which had not been thoroughly investigated.

But West Yorkshire Police has insisted that officers had carried out an "extremely thorough" inquiry.

Miss Fox, 43, of South Parade, Cleckheaton, said: "I want the police to reinvestigate the case. They have not kept me informed through all this and I have not been allowed to see any statements relating to the accident.

"I accept Anthony had some responsibility for what happened. I just don't think all the blame should be put on him. At the end of the day they were all kids and I don't want to blame anyone. But I believe the owner of the bike should also take some responsibility.

"Anthony would not have hurt anybody intentionally. I believe his riding that night was due to inexperience rather than recklessness."

Miss Fox said Anthony and Natalie had been devoted to each other.

Miss Fox has spoken to her solicitor about the possibility of seeking a reinvestigation.

Anthony's sister Leah Bentley, 15, said: "Anthony was the best brother you could ask for. He was not a reckless driver. He loved his girlfriend very much."

West Yorkshire Police said: "This is clearly a tragic incident and our thoughts are with the families involved. The investigation into the collision was extremely thorough. Inquiries were done at the scene and established beyond all doubt that the motorcycle was the only vehicle involved.

"Three people were riding the motorcycle, which was designed for a maximum of two."

e-mail: steve.wright@bradford.newsquest.co.uk