Cambridgeshire serial killer Joanna Dennehy took a grinning photograph of herself as she searched out further victims.

The picture, shown to jurors in the trial of her two alleged accomplices, shows the 31-year-old murderer posing and sticking out her tongue in the back of a Vauxhall Astra moments before she selected and stabbed her fourth and fifth victims.

Jurors have also been shown pictures of Dennehy smiling and posing with a knife shortly after murdering the men.

Dennehy had already killed three men in Cambridgeshire when she randomly targeted the two dog walkers in Hereford.

Both men suffered multiple injuries but survived.

Mark Lloyd, who was in the same car as Dennehy and her alleged accomplice, Gary Stretch, told Cambridge Crown Court Dennehy had been driven by a thirst for blood.

Describing the attack on the first man, Robin Bereza, he said: 'I thought she was going to mug him but then it twigged on me. I thought, 'You just want blood'.'

Jurors were also shown CCTV footage of Dennehy taken in Green Lane Stores, Hereford, moments before the April 2 attacks, on which she is seen laughing and joking with Mr Lloyd.

Mr Lloyd said he had considered telling the shop assistant to call the police and raise the alarm about her plans to carry on the killing spree but added: 'I wanted to say something but there wasn't the time.'

A wanted appeal had been issued to trace Dennehy and Stretch following the murders of Lukasz Slaboszewski, 31, John Chapman, 56, and Kevin Lee, 48, who were found dumped in ditches near Peterborough in March and April last year.

She had bragged to friends that she and Stretch were like Bonnie and Clyde, the court has heard.

Cross-examined by Stretch's counsel Karim Khalil QC, Mr Lloyd said he was scared of Dennehy and had no choice but to join the pair on the journey to Hereford, adding: 'If she had told me to put my head through the windscreen, I would have done.'

Dennehy, of Orton Goldhay, Peterborough, has admitted murder.

She has also admitted the attempted murders of Mr Bereza and John Rogers and preventing the lawful and decent burial of all three murder victims.

Stretch and another man, Leslie Layton, are standing trial accused of helping her dispose of the bodies and covering up her crimes.

Describing the moment he found out the pair were wanted by police, Mr Lloyd said: 'I thought it was Gary who done the murders because he's 7ft 2in and looks like Herman off The Munsters.

'She looks like butter wouldn't melt until she opens her mouth.'

Mr Lloyd told the court that, as they made their way to Hereford, Dennehy said: 'I want to have my fun.'

Stretch, real name Gary Richards, 47, of Riseholme, Orton Goldhay, Peterborough, denies three charges of preventing the lawful burial of all three men and two counts of attempted murder.

Layton, 36, of Bifield, Orton Goldhay, denies perverting the course of justice and two counts of preventing the lawful burial of the bodies of Mr Chapman and Mr Lee.

The trial continues.