Engineer John Tarpey told the court that "in my professional opinion" calls had not been made from the upstairs of Liam Cromie's Waldon Street home in Preston, or from his grandmother's home nearby.

Cromie denies the murder of David Cornall, who was fatally stabbed after being attacked close to his home on Hesketh Close, Preston.

However, Mr Tarpey accepted he had not made detailed checks from those exact locations, the court heard.

Andrew O'Byrne, defending, said the tracking of calls was "not an exact science".

Mr O'Byrne said: "You cannot say conclusively the calls were not made from upstairs at 15 or 18 Waldon Street."

The expert accepted he could not.

Mr Cornall, 30, was walking home from Preston when he suffered a single stab wound.

He managed to stagger home, but died hours later, in February, despite emergency surgery at the Royal Preston Hospital.

Mr Tarpey had detailed calls and the locations from a mobile which the prosecution says was used by the defendant.

Cromie claims he was at his grandmother's home that night on Waldon Street, Callon, before going to his own home nearby, also on Waldon Street.

Secret recordings of conversations from inside the defendant's house made before his arrest in March were replayed to the jury.

It is the prosecution's case that the conversations show that the defendant admitted being responsible for the knifing.

Cromie pleads not guilty to murder.

(Proceeding)

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