Six fire engines were sent to reports of a fire on the top of the Royal Sussex County Hospital this afternoon – but the fire service says all they found was steam.
Several people called East Sussex Fire and Rescue Service from 4.39pm after seeing what they thought was smoke coming from the helipad.
Others saw a bright light coming from the top of the building.
But by 4.55pm, firefighters had established that all that was escaping from the roof was steam.
A spokeswoman said: “We have classed this as a false alarm with good intent.”