Polish police say they have shut down one of the biggest piracy operations in Europe.

Police suspect the operation-which had an estimated distribution of nine million albums-was behind the Masterbox series, which consisted of DVDs containing pirated product, and featured more than 40 music albums over 38 editions, the last 15 of which were pressed in Poland.

According to the IFPI, the trade value of the music in the Polish editions is thought to be around €19 million ($24.4 million). Titles featured in the series included Razorlight's "Slipway Fires" and Andrea Bocelli's "Incanto."

DVDs including pre-release versions of blockbuster films "Slumdog Millionaire" and "The Wrestler" were also seized.

Four people have been detained for questioning by officers in Warsaw and southern Poland, including a 38-year old man believed to have masterminded the operation. Three premises -- two replicating plants in Warsaw and Rybnik, and a professional distribution plant in Zabki -- were raided in the sting.

The activity was uncovered by the IFPI and Polish recording industry association ZPAV, and reported to local authorities.

"This was a lucrative criminal enterprise that was based in Poland but exported pirate music and film to other EU countries," said Len Hynds, head of the IFPI's enforcement unit, in a statement. "The decisive action shown by Polish police shows the country is no safe haven for such criminal enterprises.

"Organized criminal gangs often regard counterfeit entertainment products as a low-risk revenue stream. These raids send a clear message that such a calculation is a serious mistake."

Meanwhile, in Glasgow, Scotland, seven men and two women have been arrested in connection with a counterfeit operation raid that uncovered thousands of DVDs worth an estimated £350, 000 ($497, 000) and over 100 DVD burners.

Local police and the Federation Against Copyright Theft (FACT) carried out the investigation.