Ian Metcalfe, 34, has denied murdering his two sons Dylan Lockerbie and Kyle Metcalfe, who died eight years apart.

Paediatric radiologist Dr Jeanette Mackenzie told his trial at the High Court in Edinburgh that police had asked her to prepare reports on the x-rays of the two children.

The infant is picked up and the chest is gripped with an adult's hands

Dr Jeanette Mackenzie

She said Kyle had sustained fractures at the junctions of four ribs, which she thought were about two weeks old.

Dr Mackenzie said that when she had seen this type of injury in the past it had been in cases of non-accidental injury.

"What happens is that the infant is picked up and the chest is gripped with an adult's hands," she said.

"The child's chest is squeezed and the child is actually shaken."

She said the injuries were "almost certainly" not due to attempts at resuscitation.

'Gripping and squeezing'

She said that Dylan's x-rays had shown three fractured ribs which she estimated were three weeks old.

There were also a further six fractures to the ribs which Dr Mackenzie thought were more recent than the three-week-old injuries.

Asked for her view on how the two children sustained their injuries, she said: "By gripping and squeezing the child's chest."

Ian Metcalfe has denied the charges

Advocate depute Edward Targowski QC asked if that was a non-accidental injury, to which she replied: "Yes."

Mr Metcalfe is accused of asphyxiating two-month-old Kyle at his former home in Waterfoot Road, Annan, in Dumfriesshire, on 27 January 1988.

He is also accused of suffocating five-month-old Dylan at his house at Rashgill, Locharbriggs, Dumfries, on 12 March 1996.

Mr Metcalfe has also denied attempting to murder both children and twice attempting to murder a third baby boy, who cannot be identified for legal reasons, in 1989.

During the second week of the trial, the jury was told by a social worker that a case conference on Dylan on 17 November 1995 had decided not to put him on the child protection register.

No visit

Instead, a referral was made to a Dumfries family centre for help in handling the child.

No-one visited Mr Metcalfe and his partner Maureen Lockerbie until 12 December.

Shona Bain, 48, said this was an "acceptable" length of time to wait.

She said she did not think she had been informed that the family wanted support there and then.

'No support identified'

Defence counsel Donald Findlay QC described this as "a gross failure".

She denied that it was a failure - but admitted that "in real terms" the centre had probably done nothing to help and support the couple before Dylan's death.

"There was no support identified. They were managing. They were coping," she said.

Mrs Bain also denied that she had deliberately tried to play down the distress of Mr Metcalfe.

The trial, before Lord Carloway, continues.