Police have seized more than 10,000 "weapons of war" – destined for criminal and terrorist groups in Europe – in one of the biggest arms hauls in history.
Armoury: One of world's biggest
Spain's Policia Nacional, with help from Europol, announced in January it had made a major weapons haul but has only now released pictures and a final tally of the results of their operation against firearms trafficking.
The joint forces blamed the time it took to compile an inventory for the delay in disclosing the arsenal of 9,000 CETME rifles, 1,000 brand-name rifles, 400 howitzers, anti-aircraft machine guns, shells and grenades.
Among the cache, officers also found hundreds of pistols and revolvers due for modification and "reactivation", as well as spare parts, machines for repairs, tools for changing the weapons' serial numbers and devices for falsifying documents in an illegal workshop.
The weapons were found in the Spanish city of Girona and in undisclosed locations in the provinces of Biscay and Cantabria. Five people have been arrested.
Europol said the organised crime group sold deactivated firearms which did not comply with existing deactivation standards, as well as live-firing firearms.
"The armament was acquired mainly through legally established channels," a statement said. "The dismantled group, made up of five people who were arrested, bought out-of-commission weapons which they then reactivated and sold to organised crime groups and terrorist organisations."
It was concluded the weapons were destined for the black market, given their type, calibre and automatic nature and the fact they could be easily reactivated on delivery and with the addition of parts shipped separately.
Europol said the group sold weapons into Spain and other European countries like France and Belgium. A large part of the haul was Spanish-made. Police also found an illegal workshop near the northern city of Bilbao with tools to manipulate and reactivate weapons.
A sports store was reportedly used as a front for the group's distribution centre and £70,000 in cash was also seized.
"The seized weapons had an easy journey in the black market and posed a significant risk of being acquired by organised crime groups and terrorists," the law enforcement agency said.
Investigators from Operation Portu arrived at the arsenal while tracing weapons used in a terrorist attack at the Jewish Museum of Belgium in 2014, which killed four people.
French national Mehdi Nemmouche was arrested in Marseille in southern France on May 30, 2014, on suspicion of having carried out the attack.
Prosecutors said he was carrying a Kalashnikov, another gun and ammunition similar to that used in the shooting.
The attack prompted police forces across Europe to step up their investigations into illegal weapons sales.
In 2014, police in China claimed a record haul of around 10,000 guns and 120,000 knives.
The latest United Nations report on the global trafficking of weapons shows Mexico and Brazil seized 14,467 and 13,048 weapons in total each in 2013. Only Colombia seized more weapons that year – 38,236 – with most other countries reporting less than 4,500 weapons confiscated yearly.