German police say 25 people have been injured, four of them severely, after an explosion destroyed a building in the western city of Wuppertal.

Police say the explosion rocked the several-storeys-high building shortly before midnight on Saturday with a large noise, scaring people in surrounding homes so much they ran out into the street in a panic.

Fire broke out in several different parts of the house and firefighters had trouble dousing the flames because parts of the building kept collapsing.

Police say the explosion rocked the several-storeys-high building shortly before midnight on Saturday with a large noise, scaring people in surrounding homes so much they ran out into the street in a panic

Workers of the THW technical relief service inspect the debris of a house that has exploded in the night in Wuppertal, western Germany

Firefighters battle to extinguish a fire at an apartment building in Wuppertal, Germany, late last night

Police described the scene as a 'picture of devastation'. A spokesman added: 'How this came to pass and what the background is, that remains completely unclear'

They were able to rescue four severely injured people from inside the building.

Another 21 people were slightly injured and treated by emergency staff at the scene.

Emergency services said on Sunday they were still trying to get the fire under control.

They are investigating the cause of the explosion.

Emergency services said on Sunday they were still trying to get the fire under control. Pictured: The damaged building

They were able to rescue four severely injured people from inside the building. Another 21 people were slightly injured and treated by emergency staff at the scene

Fire broke out in several different parts of the house and firefighters had trouble dousing the flames because parts of the building kept collapsing

Police described the scene as a 'picture of devastation', according to DW.

A spokesman added: 'How this came to pass and what the background is, that remains completely unclear.'