German and Turkish police said Wednesday they broke up a sophisticated smuggling ring that had been trafficking primarily Syrian refugees across the Mediterranean in freight ships into Europe.

In a series of early-morning raids coordinated across both countries, authorities arrested 35 suspects — five in Germany and 30 in Turkey, officials from both countries said at a news conference in Germany.

"Today, together with our Turkish friends, we dealt an important blow to smugglers without scruples," said Dieter Romann, head of Germany's federal Bundespolizei.

The joint investigation was begun at the end of 2014 after the ring was linked to the smuggling of 1,766 people who were put aboard three ships that were set to autopilot, and then sent toward the Italian coast. The refugees, who arrived safely, usually paid between $4,500 to $6,000 per person, German police said.

Raids in Germany were carried out by nearly 500 officers, including special tactical units, searched 16 homes and one business in six states. In Turkey, police raided 10 homes in Istanbul, Mersin, Izmir and Hatay and arrested 30 people, as well as confiscating computers, tens of thousands of dollars in cash and other evidence, Turkish national police chief Mehmet Lekesiz said.

The five people arrested in Germany were primarily Syrians themselves, including two who were currently awaiting asylum, police said.

Turkey is the main transit country for migrants from the Middle East, Asia and Africa trying to reach Europe, and Germany has been working closely with Ankara to try and stem the flow.

Two others linked to the ring were arrested in a joint German-Italian investigation in August, and turned over to Italy for prosecution, German police said.

The joint Germany-Turkey investigation is ongoing.