German police found 700 guns and more than 2.2 tons of ammunition in the home of a 54-year-old illegal gun trader last month, investigators announced Monday. It took police two days to clear out the rifles, pistols and ammunition the man was hiding in the home where he lived with his wife and son in Schwerte, police said.

While police did not specify the types of weapons seized in the raid, the man regularly sold to hunters and collectors, the Associated Press reported. While there is no precise number, German officials estimate there to be 17 million illicit firearms in Germany, compared to the 7 million or so registered firearms in the country. Illicit firearms include both illegal military-grade weapons like fully automatic rifles and unregistered civilian-grade weapons. The German government requires gun owners to have “a need for a weapon” and recognizes collectors, hunters and marksmen as having such a “need.” Unlicensed gun owners can face a maximum penalty of 10 years in prison.

The European Union has stepped up efforts to control illegal gun trafficking following the brazen terror attacks in Paris in January that left 16 dead. The assailants, three French residents, were equipped with automatic assault rifles and military-grade equipment. Many military-grade weapons like Kalashnikov rifles originate in or are smuggled into the EU through the Balkan states where there are millions of guns left over from the wars among the former Yugoslavian states. The EU Schengen Area’s open border policy allows these weapons to cross borders relatively easily. A fully automatic Kalashnikov can be found for as little as 1,000 euros in France.

Civilian-grade weapons on the other hand are often stolen or were once-legal firearms that were illegally “reactivated” by sellers and sold under the table. The man in Schwerte did not have a valid license, but was using a friend’s license.