A former Great Ormond Street Hospital porter has admitted sexual offences against six boys over 35 years.
Paul Farrell, 55, pleaded guilty to 58 sex offences against children carried out between 1985 and 2020.
The charges relate to six victims, who cannot be named, who are now aged between eight and 43.
Farrell, from Camden, appearing at Wood Green Crown Court, admitted charges including attempted rape and the sexual assault of a child aged under 13.
He pleaded guilty to 33 charges, having previously admitted 25 counts at an earlier hearing.
He has denied a further 21 charges, including rape.
The court heard Farrell held a number of positions, including working as a porter at Great Ormond Street Hospital (GOSH) between 1994 and 2020.
At least two victims allege they were sexually abused by Farrell at the hospital.
Judge Noel Lucas said: "The prosecution have made it clear that this is not a case where it is alleged that Mr Farrell was targeting children at the Great Ormond Street Hospital.
"Rather that children were abused in parts of the hospital in which he had access."
Police arrested Farrell on 16 January.
According to the charges, Farrell continued to offend until June this year.
One boy, under the age of 13, says he was sexually assaulted "during lockdown".
In a statement the hospital said: "These charges relating to a former member of GOSH staff are awful.
"It is upsetting to hear in court today that some of the charges relate to the hospital site.
"It is important to stress, as stated by the judge today, that GOSH patients were not targeted.
"Due to the ongoing legal proceedings, we are really limited in what we can say, but we can confirm again that Paul Farrell was dismissed from the Trust."