Stores in western Sweden have been returning bottles of Loka water to Coca-Cola and asking for compensation after receiving complaints from customers about a foul smell, The Local.se reported Saturday.
Several individuals have filed direct complaints with Coca-Cola after purchasing drinks which they said both smelled and tasted badly.
No one has become ill from consuming the soft drinks, the news report said.
Police have started an investigation into potential poisoning of the drinks.
Coca-Cola spokesman Peter Bodor told the local TTELA newspaper: "We regard the situation as very serious. Production here in Jordbro [in the south of Stockholm] started 14 years ago and we have never experienced this before. Those who have contacted us say that the Coca-Cola smells and tastes strangely. This is very serious."
Bodor said the company has sent some of the bottles out for testing, but as far as Coca-Cola knows, there has been no wrongdoing.
"We have scrutinized every part of the process and cannot find any faults. Our Coca-Cola product reaches the whole country, but all the complaints come from the same geographical area," Bodor said.