Hamburg’s fire brigade has issued an “extreme danger” alert as a cloud possibly containing “chemical components” drifts towards the city centre.
The German city’s authorities are advising people to avoid the area and told residents to close doors, windows and ventilation.
It comes after a fire at a storage facility in the Rothenburgsort district that forced 140 people to evacuate.
Police say it is not possible to say how dangerous the situation is.
Multiple police, fire and other emergency workers were at the scene as a thick cloud of smoke billowed upwards.
There are no reports of any casualties.
Local public broadcaster NDR reported that the fire broke out at 4.30am at a truck stop.
Image: Pic: AP ‘Extreme danger’
A spokesman for the fire brigade told NDR Hamburg’s city centre was “completely blacked out” when the fire broke out.
Hamburg police said the smoke was classified as an “extreme danger” and recommended residents “drive around the affected area as far as possible.”
Image: Police walk along the tracks of Hamburg-Rothenburgsort station. Pic: AP On Sunday morning the national railway company Deutsche Bahn also announced a closure between Hamburg and Buchen due to the fire.
The railway said trains between Hamburg and Berlin will be diverted and delayed by around 90 minutes.