A top Scotland Yard police officer today told the Sharon Beshenivsky murder trial how he had an hour-long meeting in a car with one of the accused who had approached him with information.

Superintendent Chula Rupasinha, a metropolitan police officer for 26 years, said that Raza Ul-Haq Aslam, whose family lived two doors away from him in London drove him to a side street 18 days after the robbery and shooting in Morley Street, Bradford, and told him he had heard his fellow accused Muzzaker Shah, was in Wales.

Supt Rupasinha told Newcastle Crown Court that Aslam had intended to get Shah's mobile phone number through a third party and give it to the officer so he could pass it on to West Yorkshire Police.

But the officer said the offer was conditional on him not disclosing that Aslam was the source of the information and he told him he could not do that.

Supt Rupasinha said he tried to persuade Aslam to co-operate in an open way but he could not achieve that because Aslam did not trust police to keep his identity secret and he was in fear of his life from Shah and his associates.

The officer said that he encouraged Aslam to go to the police and not to get the third party's mobile phone because he had no authority to do that and it was potentially dangerous.

He said he suggested Aslam met him and a detective in a car to give this information but Aslam would not accept that idea.

He also encouraged him to be an informant but Aslam kept emphasising the brutality of the people he was proposing to give information about.

Supt Rupasinha said he eventually suggested Aslam contacted Crimestoppers and used a pseudonym.

He told the court: "I said to him that would get him a reward if that was his motivation, but also it would be helpful to the Crimestoppers people and investigation team. I felt it was much more efficient and something I encouraged him to do. He said I will use the name Alex."

Supt Rupasinha said Aslam knew Crimestoppers used pin or serial numbers to pay rewards and said he noticed an animation in his behaviour when the reward was mentioned.

Yusuf Abdillh Jamma, 20, of Small Heath, Birmingham, Raza Ul-Haq Aslam, 25, of Kentish Town, London, and brothers Faisal Razzaq, 25, and Hassan Razzaq, 26, both of Forest Gate, London, plead not guilty to PC Sharon Beshenivsky's murder.

Aslam and the Razzaq brothers deny robbery but Jamma has admitted that charge. Aslam, the Razzaq brothers and Jamma also plead not guilty to firearms offences though Jamma admits two charges of possessing a prohibited weapon.

Muzzaker Imtiaz Shah, 25, of London, admits murder, robbery, two charges of possessing a prohibited weapon and two charges of possessing a firearm with intent to endanger life. He has been acquitted of the attempted murder of PC Teresa Milburn.

The trial continues.