She is Britain's most prolific serial child killer in modern times.

The 33-year-old murdered the five baby boys and two baby girls at the neonatal unit of Countess of Chester hospital in northern England over 13 months from 2015.

She injected the infants with insulin or air, or force fed them milk.

Letby refused to leave the cells to hear the sentencing delivered by Judge James Goss.

"This was a cruel, calculated and cynical campaign of child murder involving the smallest and most vulnerable of children, knowing that your actions were causing significant physical suffering and would cause untold mental suffering.

"You removed and retained confidential records of events relating to your crimes and checked up on bereaved parents. There was a deep malevolence bordering on sadism in your actions."

Some of those she attacked were twins - in one case she murdered both siblings, in another she killed two of three triplets.

In two instances she murdered one twin but failed in her attempts to kill the other.

A handwritten note reading "I AM EVIL, I DID THIS" was found during a police search of her home after her arrest.

Whole life orders are very rare, and only three women in Britain have received such a sentence before.

They include serial killers Myra Hindley and Rosemary West.

The harrowing crimes committed by Letby, who was in her 20s when she carried out her killing spree, have horrified Britain.

Earlier the court heard emotional, heart-wrenching statements from the parents of those she murdered and tried to kill.

The mother of one murdered baby boy said: "There is no sentence that will ever compare to the excruciating agony that we have suffered as a consequence of your actions."