Commuters faced severe disruption after a large fire in a disused city centre building.
Fire crews remained at the scene of the blaze in central Nottingham as rush hour approached, causing "significant disruption" to the city's tram network, police said.
Crews were called to the scene, at a premises in Goldsmith Street, shortly after 1am and 1,400 people were evacuated from a nearby nightclub.
Inspector Ian Cresswell, of Nottinghamshire Police, said: "Nobody has been hurt as a result of the fire and people were evacuated as a precautionary measure for their personal safety.
"The fire has now been contained and we are continuing to assist the fire service while they carry out their work at the scene."
Police said Goldsmith Street and Talbot Street were both closed to pedestrians and vehicles, and asked motorists driving into the city centre to "be patient". Tram services into the city centre from all directions were also suspended, a police spokesman said.
Police said student accommodation near the scene was evacuated, as well as The Rescue Rooms nightclub, where a student event was taking place.
A spokesman said: "Nottinghamshire Police would like to thank members of the public for their patience and co-operation."