A father accused of shaking his six-week-old baby to death has told murder jury he "can't explain why" he caused the injuries.

Lee Vernon has admitted manslaughter and two counts of causing serious injury to McKenzie Ellis at Broadstairs in July last year. But he denies murder and two charges of inflicting GBH with intent.

Baby McKenzie died from a bleed on the brain at King's College Hospital in London, having sustained 18 breaks to his ribs and 10 elsewhere.

Prosecutors allege Vernon caused the fatal head injury by shaking the baby boy, but the 21-year-old claims it occurred when he accidentally dropped McKenzie.

"I accept that I caused all the injuries which led to my son's death... but I can't explain why," he told Maidstone Crown Court.

He added: "I did not intend to kill him or cause him any serious injuries.

Defence barrister Paul Mendelle QC asked the 21-year-old, from Linley Road, Broadstairs: "Did you ever intend to kill or cause your son any serious injury?"

Vernon - one of eight children from Derby - told Maidstone Crown Court: "No."

He said he had been brought up in care after the break of his parents' marriage and therefore was reluctant to involve social services when his child was born.

Vernon said he moved from Dover to Margate in 2015 and in November met Mackenzie's mother Katrina, a 15 year old schoolgirl, after a post he put on Facebook.

He said it wasn't sexual and after splitting up they got back together the following year when she was 17 when it became sexual.

Vernon worked two-days a week for Invicta Produce before moving to a full time job at a B&Q store at the end of 2017.

"We found out Katrina was pregnant after taking tests. It was unplanned but I was happy. We had a conversation about whether we wanted a child and we both agreed we did."

Vernon, who was living in foster care at the time, said they did not got for parenting classes.

"After I cut the baby's chord I proposed to her and I bought a ring from Argos. I wanted to marry her because I love her.

"I had asked her father's permission first and as she lay in the bed in the delivery room I got onto one knee and proposed. I was ecstatic when she agreed."

The prosecution has alleged Vernon "intentionally inflicted non-accidental injuries on his son", resulting in a fractured skull and the bleed on the brain.

McKenzie was taken to the QEQM Hospital on July 23 after collapsing at Vernon's home.

He was transferred to Kings College Hospital in London but never recovered and died three days later, aged just 47 days old.

The jury have been given an eight-page document showing computer-generated images of the injuries McKenzie sustained before his death.

The UK's only forensic bone expert, Professor David Mangham, says he believes they were caused deliberately.

"The number of fractures and re-fractures indicate, in my opinion, they were non-accidental injuries," he told the jury.

He believes partial fractures to five of the baby's ribs occurred between three and seven days before McKenzie's death.

He added some of the injuries could have been sustained up to three weeks before.

There were also fractures to the baby's left collarbone, right femur and left ankle, caused between three to five days prior to his death.

Prof Mangham said some of the back ribs had been broken, including some which were "re-fractures".

He said one of the ribs had a fracture that was a "non-accidental" injury, telling the jury that "substantial force" would have been needed to cause compression fractures to the baby's chest.

He added that some of the causes of the fractures included bones being pulled apart, as in a "swinging, pulling and twisting" action.

Other injuries were typical of "classic shaken baby syndrome", he told the court.

"The injuries caused include whiplash and also blunt-force injuries," he said.

Vernon claims he accidentally dropped the baby, saying McKenzie collided with the wooden arm of a chair before falling to the ground.

But the prosecution say he is a "manipulative liar who is able to provide a convincing account which is inconsistent with the medical opinion".

The trial continues.

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