Police and state prosecutors in nearby Cologne in North Rhine-Westphalia are investigating a xenophobic motive to the attack, in which nine people had to flee a ground-floor apartment after assailants hurled several fire bombs through the windows around 12:25 am Monday.
All nine people in the apartment escaped unharmed but the apartment was totally burnt out by the blaze and only the intervention of the fire brigade stopped it destroying the rest of the building.
The attack came amid a heightened atmosphere surrounding far-right violence in the wake of the massacre of at least 76 people on Friday by a Norwegian nationalist.
Witnesses saw two young men wearing dark clothing fleeing the scene in a dark Volkwagen car, possibly a Golf or Polo, with number plates from the NRW city of Neuss, police reported. Daily Bild reported that the fleeing suspected had shaved heads.
A police spokesman confirmed to The Local on Tuesday morning that investigators were continuing to probe the possibility that right-wing extremists were behind the attack, though all avenues were being examined.
Twenty-one officers from the Cologne police, including members of the arson squad, were investigating.