A suspicious vehicle had been spotted overnight on Friday by security staff tasked with monitoring the grounds of Leeds General Infirmary, where the children’s hospital is based.
But it was only as it became light in the early hours of Saturday that estates staff discovered the theft and damage.
They found cables leading to the emergency generator put in place for the children’s hospital had been stolen.
West Yorkshire Police yesterday issued an appeal for information, saying that the stolen cables were worth thousands of pounds.
A spokesman added that security patrols had been increased on the hospital site and CCTV footage was being reviewed.
The vehicle which raised suspicions was described as being a ‘red Transit-type’ van.
Meanwhile, Leeds Teaching Hospitals NHS Trust said repairs to the generator had already been undertaken.
A spokeswoman said: “We were made aware of an incident at the children’s hospital in the early hours of Saturday morning where some temporary generators were damaged.
“Our on-site contractors worked quickly to make the necessary repairs the same day. Thankfully no hospital services were affected by this incident.”
It is not the first time that the children’s hospital, which is one of the largest in the UK, has been targeted by thieves.
The parents of a terminally ill boy were jailed in February 2016 after stealing and selling laptops from a cancer ward.
The laptops, funded by the Candlelighters charity, were cut from children’s bedsides.
Leeds General Infirmary was also revealed to be one of the top 10 hotspots for crime in the city.
More than 440 incidents were recorded in the three years to September 2016, although the majority were alcohol-related and took place in its 24-hour A&E department.
Anyone with information on the cable theft is urged to call police on 101, quoting crime reference 13170416482.