Aachen (dpa / lnw) - Because of bacterial contamination of the drinking water, the Stadtwerke Aachen recommended that the city's citizens boil tap water as a precaution.

The contamination was found during a routine inspection, the municipal utilities announced on Tuesday evening.

"If you let the water boil for three minutes, you can then use it completely harmlessly to prepare food, also for children, old and sick people, to wash off food, to make ice cubes, to brush your teeth and for medical purposes", it was said.

The tap water can be used for personal hygiene without boiling.

The cause of the contamination is still unclear, said a spokeswoman.

How long the recommendation will apply is currently not known either.

© dpa-infocom, dpa: 210126-99-181453 / 2