A secretive group dedicated to overthrowing Kim Jong-un was behind a raid on Madrid’s North Korean embassy just days before a high-profile summit with Donald Trump, according to US media.

Ten men burst into the compound on February 22, tied up staff, stole computers and documents before escaping in two luxury vehicles.

According to the Washington Post, the operation was carried out by a group called Cheollima Civil Defense, a secretive dissident organisation committed to overthrowing the Kim dynasty.

Experts believe the stolen documents could provide insight into North Korea’s efforts to bypass international sanctions and import luxury goods from Europe. Those files could be a veritable treasure trove for intelligence agencies, who may seek access to them from the group.

The raid has been shrouded in mystery and was initially reported as a break-in. Spanish authorities have only officially confirmed that on February 22 a North Korean woman who was slightly injured was picked up on a street near the embassy.