The mayor of Blankenburg Heiko Breithaupt told reporters at a press conference that 11 people had been injured, despite earlier police estimates putting the figure at around 25.
One of those was seriously hurt, while nine had escaped with light injuries and another had sustained more serious injuries, Breithaupt said.
The mayor added that the building was now a “scene of devastation”.
Local police chief Frank Götze said that the person killed had not yet been identified, but said the victim may be the owner of the apartment in which the explosion happened.
Police were also unable to say if the blast was deliberately set off or if it was an accident.
Götze said the explosion was probably caused by gas canisters found at the scene.
Yet he added that it was unclear why the gas canisters were there, given that the building was supplied by a district heating system.
— Polizei Magdeburg (@Polizei_MD) December 13, 2019
The explosion struck shortly before 9am at a five-storey building with 60 apartments, sending splinters flying up to 60 metres away.
Residents in the building have been evacuated, police said, with one family transferred to emergency accommodation.
A closer view of the damaged apartment. Photo: DPA
Breithaupt said police were at the scene, and that investigations could continue “well into the night”.
A nearby kindergarten was also evacuated, with around 100 children being taken out of the facility.
Blankenburg is located in the Harz region and has about 20,000 residents.