'Trust Me, I'm a Nurse': Mom Walked in on Nurse While She Was Allegedly Murdering Her Son

In August 2015, an already worried new mother of premature twin boys was shocked to see one of her five-day old sons "acutely distressed" and bleeding from the mouth in the neonatal unit of a U.K. hospital, a prosecutor told a British court.

The nurse tending to the infant allegedly told the terrified mother not to worry: a nasogastric tube had simply irritated the infant's throat, prosecutor Nick Johnson told the Manchester Crown Court, the BBC, The Guardian and The Independent report.

"Trust me, I'm a nurse," Lucy Letby allegedly told the shaken mother, Johnson said.

The infant, who weighed less than 3 lbs. and who prosecutors are calling Baby E, died five hours later, allegedly at the hands of Letby, 32, who is accused of injecting air into his bloodstream.

Arrested in July 2018, Letby is on trial after being charged with killing five baby boys and two baby girls and attempting to kill 10 others in the neonatal unit of the Countess of Chester Hospital in Manchester between June 2015 and June 2016, the BBC reports.

Letby has denied all the allegations.

Johnson told the court that on Aug. 3, 2015, the new mother, who has not been identified, had no idea that Letby was in the process of allegedly murdering the infant when she walked into the room to bring her sons milk.

The mother "interrupted Lucy Letby who was attacking [Baby E]," who was "acutely distressed" and bleeding from the mouth, Johnson told jurors.

The mother left after being "fobbed off" by the alleged baby killer, he said.

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Letby allegedly told the mother that another medical professional would check on the infant — and that she needed to leave the neonatal unit, Johnson told the court, The Independent reports.

No autopsy was performed because hospital officials attributed the infant's death to a condition that premature babies sometimes have, The Guardian reports.

Letby also allegedly tried to kill Baby F, the infant's twin brother, by injecting him with insulin and trying to poison him, Johnson said.

Calling Letby a "malevolent presence" in the hospital, Johnson said Letby allegedly tried to hide her actions by falsifying her notes, which were "designed to cover her tracks."

While Letby has said she is innocent, on Thursday the prosecution presented several handwritten notes in which she allegedly confessed to killing the babies.

In one note, she allegedly wrote, "I killed them on purpose because I'm not good enough to care for them," Johnson said.

In another, she allegedly wrote, "Not good enough. I will never have children or marry. I will never know what it's like to have a family."

She also allegedly said in one of the notes, "I am a horrible evil person" and then wrote in capital letters: "I AM EVIL I DID THIS."

Her trial continues this week.

Her attorney could not immediately be reached for comment.