Authorities have reported yet another case of suspected tampering with a water supply close to a military base. Some 10,000 residents were told not to drink water while tests were carried out.

German authorities told residents of a town in the west of the country to avoid using or consuming water from the taps on Thursday afternoon amid fears that the water supply had been tampered with.

The warning came after a hole was found in the fence around the supply, which also feeds a nearby military base. The warning was partially lifted on Monday, but residents were told to boil tap water before drinking it.

The incident in the town of Mechernich, in the western state of North Rhine-Westphalia, was discovered after another suspected case of sabotage was reported close to a military baseat Cologne airport, not far from the town of Mechernich.