Careless use of liquefied petroleum gas (LPG) caused a cylinder to leak, which triggered a deadly blast in an apartment building in the Northeast province of Heilongjiang, local authorities said Monday.

The blast occurred at 4:50 am Saturday on the sixth floor of a building in the city of Mudanjiang, killing six residents, injuring four others and damaging parts of the building.

A total of 105 families living in the building and nearby were evacuated, and had temporarily moved in with relatives or were staying in hotels, a spokesman with the Mudanjiang municipal government said.

Local authorities are assessing the current condition of the building, he said.