They said they had smashed a drug ring that operated between Leipzig and Prague in the Czech Republic.
Around 2.3 tonnes of crystal meth can be made out of the amount of chloroephedrine that was seized by the German-Czech joint task force, the Federal Criminal Police Office (BKA) said in a press release.
The street value of that much crystal meth is €184 million.
"Given that in 2013, the total amount of crystal meth seized (by the BKA) was around 80 kilogrammes, the seizure of nearly three tonnes of chloroephedrine that was to be made into methamphetamine is a clear sign of our success," said BKA president Jörg Ziercke.
Ten kilogrammes of the chlorephedrine had already been manufactured and was about to be shipped to from Leipzig to the Prague branch.
In the course of the BKA's investigation, it found that the chloroephedrine was sent from Leipzig to Prague in 10 to 20 kilogramme batches and processed into the crystal meth there. It was then sent back to Germany and distributed.
An October 2014 seizure of four kilogrammes of crystal meth established a connection between a 32-year-old pharmaceutical wholesaler and the drug manufacturer in Prague. He is believed to be the ringleader.
He and seven others were arrested by German police. Czech authorities took another seven into custody as a result of the investigation.
"The successful teamwork with Czech authorities shows how important and indispensable international police cooperation is," said Ziercke.
According the the BKA, raids were carried out on 24 homes and businesses connected to the ring between November 5 and November 8.
Aside from the drugs and chemicals, police also confiscated money, weapons, ammunition, stolen passports and dozens of mobile telephones worth around €600,000.
The sale of chloroephedrine is legal, though only for research and experimentation purposes.