A German military base, home to thousands of troops, was placed under lockdown on Wednesday following a suspected sabotage targeting its water supply, according to Spiegel magazine. 

Officials at the Cologne-Wahn military base, which has 4,300 soldiers and 1,200 civilian employees, informed all military personnel and employees not to drink the water as they believed it had been contaminated. 

Military police and the military intelligence agency found damage to a stretch of fence on the base's perimeter, with reason to believe someone illegally entered the base. Spiegel said officials are investigating all alleged crimes.

Here's more from Spiegel:

In an internal communication from the Bundeswehr's Territorial Command (TFK), personnel still in the barracks are asked to speak to "unknown persons within sight" and to report "any suspicious behavior." This is an indication that the authorities are searching the area for possible perpetrators. Already on Wednesday night, there were internal reports from the Bundeswehr that a suspicious person had been spotted near the fence around the barracks and had fled after being discovered.

The TFK's statement also states that the barracks will remain sealed off until further notice – "neither in nor out."

A spokesperson for the Territorial Command in Berlin confirmed to Reuters that the military base was locked down but declined to provide more information on what that entailed. He said, "We have our reasons for taking this action, and we take the case seriously." 

Cologne-Wahn is a critical military hub that supports war efforts in Ukraine. It also houses military aircraft used for travel by Chancellor Olaf Scholz and his ministers.