Earlier this month Spanish National Police confirmed they are investigating a raid of the North Korean Embassy in Madrid that took place on February 22.

The group that broke into the embassy just five days before Trump and Kim’s short-lived second summit reportedly “restrained staff members with rope and stole a variety of items before fleeing in luxury vehicles.”

Though the raid initially sparked speculation of US involvement, former CIA officer Bruce Klingner doubts they would take such a risk. “If U.S. involvement were uncovered, it would jeopardize the summit, U.S.-North Korean negotiations/diplomacy, and potentially trigger a strong North Korean response,” Klingner told NPR.

Adding to a chorus of denials, U.S. State Department spokesman Robert Palladino was unequivocal in his assertion that “the United States government had nothing to do with this.”

A Spanish court unsealed new documents today revealing that among the perpetrators were a U.S. citizen and resident. Judge José de la Mata said a “criminal organization” consisting of 10 individuals carried out the raid, which involved falsifying documents and illegally detaining and injuring embassy employees.

According to an AP report, de la Mata “named Adrian Hong Chang, a Mexican citizen living in the United States, as the break-in’s leader.” Hong Chang reportedly fled to the U.S. following the raid, where he offered to share stolen material with the FBI.

The FBI declined to comment, citing its standard practice of neither confirming nor denying investigations. Spanish National Police officials said that arrest warrants have been issued for Hong Chang and another suspect.

The perpetrators called themselves “members of an association or movement of human rights for the liberation of North Korea.” The group is known by numerous names including Cheollima, Jayu Joseon, Free Korea, and other variations.

According to a Daily Beast report, the group “allegedly has the backing of some wealthy Koreans and foreigners as well as ties inside the North — apparently the first organization to have set up an operational challenge to the leadership in Pyongyang.”

The primary purpose of the raid appeared to be intelligence gathering, with a statement on www.cheollimacivildefense.org saying that “this was not an attack,” and “we responded to an urgent situation in the Madrid embassy.”

The statement, titled “Facts About Madrid” reads, in part:

We were invited into the embassy, and contrary to reports, no one was gagged or beaten. Out of respect for the host nation of Spain, no weapons were used. All occupants in the embassy were treated with dignity and necessary caution. There were no other governments involved with or aware of our activity until after the event. The Hanoi Summit had no relation to this operation. We recognize and apologize for any inconveniences caused to the authorities of Spain, who have been caught in the middle of a difficult situation. No information about Madrid was shared with any parties with the expectation of any benefit or money in exchange. The organization shared certain information of enormous potential value with the FBI in the United States, under mutually agreed terms of confidentiality. This information was shared voluntarily and on their request, not our own. Those terms appear to have been broken. Some time later, some journalists began writing speculative stories about the incident in Madrid, and the identities or affiliations of those involved, citing US government sources. That information was leaked to the media was a profound betrayal of trust. We ourselves never spoke to the media or shared any information with them.

Considering the secretive and largely anonymous nature of this organization, their claims should obviously be taken with a grain of salt. On the other hand, I also don’t find it hard to believe FBI staff promised confidentiality then turned around and leaked to the media. Regardless, this raid is a remarkable event insofar as it puts in the spotlight the previously unknown capabilities of internal North Korean resistance organizations.

Slim as their chances of overthrowing Kim Jong-un anytime soon may be, Cheollima’s ability to carry out such a dramatic operation against a nation infamous for sending relatives of defectors to prison camps is a testament to the resilience of the human spirit.