An electrical fault led to power cuts at two hospitals, an NHS trust has confirmed.
The Lister and New QEII hospitals were affected by the outage, the East and North Hertfordshire NHS Trust said.
According to the UK Power Networks website, power was disrupted just before 20:00 GMT, due to a fault to a high voltage underground electricity cable.
The firm said a number of postcodes in an area between Letchworth Garden City and Welwyn Garden City were affected before electricity was restored at 02:11.
The trust, which has been asked for further details as to how the hospitals coped with the power cut, posted on its website overnight: “Lister and the New QEII Hospitals are affected by a power outage.
“Many systems are back up and running, we are working hard to minimise the impact and keep our patients safe.”
It added maternity services remained open during the power cut.
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