PICTURES: Riverbank excavation looks for clues into disappearance of Gosport's Katrice Lee

Royal Military Police are being assisted by German authorities with police dogs in their forensic search of the banks of the Alme river, in Paderborn, senior investigating officer Warrant Officer Class 1 Richard O’Leary said.

Katrice Lee, whose mum Sharon and sister Natasha live in Gosport, vanished on her second birthday on November 28 1981, while out shopping with her mother on the outskirts of Paderborn, near the British military base where her father was stationed.

They were buying treats for a birthday party from a British military supermarket when her mother realised in the checkout line she had forgotten crisps.

The mother asked Natasha to watch Katrice and when she returned in what she has estimated was less than a minute, the girl was gone. The sister told her Katrice had run after her and she thought they were together.

WO1 O’Leary said after a new review of the evidence, he was focusing on three main areas.

Firstly, identifying a man, through a police composite, seen near the supermarket at the time of the crime with a child who looked like Katrice getting into a green car.

Second, the possibility Katrice was abducted and grew up not knowing who she was and identifying her through an age progression photo.

And third, the investigation of the Alme river area where a green car was seen on a bridge the day after the crime.

‘We’re pursuing all reasonable lines of inquiry,’ he said.

Digging on the banks of the Alme began on April 30 and is expected to last for some five weeks, WO1 O’Leary said.

He said they were looking for any ‘evidence of Katrice’s disappearance, whether that’s clothing or, unfortunately, Katrice herself’.

WO1 O’Leary said he had deemed the riverbank area to be ‘significant and of interest’ but declined to give further details.

‘As you can appreciate this is an ongoing investigation and I don’t want to release details now that might become critical later.’

He said they were also trying to trace the owners of about 500 green cars who lived in the area at the time.

‘That’s really, really difficult as you can appreciate, it was 36 years ago,’ he said, asking anyone who might have information to come forward.

Following the disappearance, broad searches of the area were conducted by British forces, German police and volunteers but no traces were ever found.

The case was featured on Crimewatch and Germany’s Aktenzeichen XY in 2017 and 2018 in an effort to ensure a wide audience saw the composite of the man with the green car and the age progression photo of Katrice.

WO1 O’Leary said the investigation has no suspects.

Authorities have been criticised over the initial investigation and the girl’s father, Richard Lee, said he was still bitter, but glad WO1 O’Leary’s team was looking into the evidence again.

‘They are doing this to try and close the gap, to try and re-instil the trust that my family has lost,’ he said.

‘Do I forgive them? The answer is categorically, no. I do not and I never will.’