BERLIN (AP) — More than 150 German and Danish police officers searched a dozen apartments and offices Wednesday in a joint cross-border raid on an illegal human trafficking network that focused on arranging hundreds of sham marriages.

In a separate but coordinated operation in eastern Germany, several locations were also searched on allegations that traffickers arranged sham marriages for foreigners trying to live in Germany without valid papers.

Police temporarily detained and questioned five German suspects in connection with the German-Danish raid, which targeted traffickers bringing people from various Asian countries to Germany, police said. Because of the ongoing investigation, police would not specify which countries the people came from.

The foreign nationals were usually matched with European Union citizens living in Germany to get them residency rights in Germany.

Police searched locations in the northern German cities of Hamburg and Bremerhaven, on the German island of Sylt and on the Danish island of Aeroe.

Merkel Effect: Thousands of Migrants Jet to Germany from Poorer EU Nations https://t.co/NiLrixmG4l — Breitbart London (@BreitbartLondon) March 12, 2018

The network may have facilitated up to 1,000 sham marriages in the last two years, federal police spokesman Joerg Ristow said regarding the German-Danish investigation.

Police confiscated marriage documents, passports, computers, mobile phones, fake residency documents and business records.

The fake marriages were mostly carried out on the Danish island of Aeroe, known as the country’s “marriage island.” For 500 kroner (79 dollars) marriages can be carried out without much bureaucracy in Danish, English or German.

In the other raid in eastern Germany, more than 100 federal police searched 27 homes and offices of alleged traffickers who are accused of bringing people from Pakistan and India to Germany, also by arranging sham marriages for them.

Searches took place in the cities of Leipzig, Eilenburg and Hettstedt, but also in some cities in the west.

Authorities say the two raids were coordinated to take place the same day to avoid causing those involved to start taking more precautions.