A nurse accused of murdering seven babies has denied harming any children as she gave evidence for the first time, crying at one point as she told the court “everything is just gone”.

Lucy Letby is also accused of 10 attempted murders between 2015 and 2016, allegedly using methods such as injecting air into the babies or poisoning them with insulin.

The prosecution alleges Letby was a “constant malevolent presence” in the neo-natal unit of the Countess of Chester Hospital in Cheshire.

The jury finally heard from the 33-year-old, seven months into her trial.

She told Manchester Crown Court on Tuesday she had probably cared for hundreds of babies at the hospital.

Lucy Letby trial as it happened

Letby said it was “sickening” when she discovered she was being blamed for a number of baby deaths while doing the job she “loved”.

“It was devastating. I don’t think you could be accused of anything worse than that,” she said.

Asked by her barrister if she ever did anything “meant to hurt any of them”, she replied: “No, I only did my best to care for them.”

Letby said she never wanted to harm any baby, saying it was “completely against everything that being a nurse is… I’m there to help and to care”.

The defendant told the court about the three times she was arrested by police, on suspicion of murder and attempted murder of babies – calling it “traumatising”.

Letby became tearful on several occasions during Tuesday’s evidence, such as when shown a photo of her bedroom during a police search.

She also appeared to cry and wipe her eyes when her barrister, Ben Meyers KC, asked how hard it was to cope with her situation.

“Everything about me and about my life, and the hopes I had for the future, everything is just gone,” said Letby – who later said she had been diagnosed with post-traumatic stress disorder.

Among items recovered during the search of Letby’s home in Chester included a Post-it note found in a diary.

Among words written on the note were, in capitals, “I am evil I did this”, the court has heard.

Letby also wrote: “I don’t deserve to live. I killed them on purpose because I’m not good enough to care for them. I am a horrible evil person.”

Mr Meyers asked her: “When you say killed them on purpose does that mean you’ve gone and done something intentionally?”

Letby replied: “No”.

Asked to explain, she said it meant she hadn’t “been good enough and that I’ve somehow failed in my duties and my competencies”.

Letby said she’d written it because “I felt at the time I had done something wrong and I thought I’m such an awful, evil person… that I had made mistakes and not known”.

Mr Myers asked: “What did you thought you had done?”

“That somehow I had been incompetent and I had done something wrong to affect these babies. I felt I must be responsible in some way,” Letby replied.

She said the scrawled note “was a way of me expressing how I felt at the time that I wasn’t able to say to anyone else”.

Family of the alleged victims – who cannot be named – watched from the public gallery as Letby gave evidence, as did her own parents.

Letby, from Hereford, denies all the allegations.

The trial continues.