The 17-year-old called Cologne police on Monday night, asking for help and saying someone was trying to kick the door in. Just three minutes later a blast rocked the building, destroying his flat completely and flinging him out the window.
A police spokesman said on Tuesday morning a 52-year-old man had “more or less confessed” after showing up at a nearby hospital covered in burns.
“He forced his way into the flat and poured a lot of petrol around the place,” a spokesman for the state prosecutor said.
They are accusing him of murder, saying he was unhappy at the teenager’s relationship with his 14-year-old daughter, Der Spiegel magazine reported on Tuesday.
A spokesman for the fire service also confirmed that two other people in the building had been slightly injured, and one of whom had jumped from a first floor window.
Members of the Cologne homicide division have taken over the case, which the Süddeutsche Zeitung newspaper said police believed to have been "caused intentionally" and is being treated as murder.