A former Marine has been arrested in Los Angeles in connection with an underground group’s raid last month on North Korea’s embassy in Madrid.

Christopher Ahn is a member of the mysterious anti-North Korea group that claimed credit for the Feb. 22 raid. Cheollima Civil Defense Group says it consists of North Korean defectors and seeks the overthrow of North Korean strongman Kim Jong Un.

Ahn appeared in Los Angeles Federal Court Friday, but the proceeding was not open to the public, The Washington Post reported. Ahn’s attorney requested that the courtroom be sealed over the government’s objection.

A Spanish police investigator in the case told The Associated Press in Madrid on Saturday that Ahn was identified by the Spanish police at a later stage of its investigation into the Feb. 22 raid and that an international arrest warrant was also issued against him.

ANTI-NORTH KOREAN GROUP CLAIMS RESPONSIBILITY FOR SPANISH EMBASSY ATTACK, SAYS FBI CONTACTED THEM FOR STOLEN DATA

In a related development, U.S. federal agents raided the unoccupied apartment of the group’s leader, Adrian Hong, on Thursday.

Lee Wolosky, a lawyer for the group, which also calls itself Free Joseon, said in a statement that he was "dismayed that the U.S. Department of Justice has decided to execute warrants against U.S. persons that derive from criminal complaints filed by the North Korean regime."

"The last U.S. citizen who fell into the custody of the Kim regime returned home maimed from torture and did not survive," Wolosky said, referring to college student Otto Warmbier's 2017 death.

"We have received no assurances from the U.S. government about the safety and security of the U.S. nationals it is now targeting," he added.

N. KOREA CALLS FOR INVESTIGATION INTO MADRID EMBASSY ATTACK

Spanish authorities said 10 Cheollima members entered the embassy and shackled and interrogated staffers, while urging the embassy’s commercial attaché to defect without success.

Intelligence officials in Spain alleged that two of the intruders had ties to the CIA.

Reuters reported that the participants fled the embassy with computers and hard drives that they presented to the FBI in the U.S.

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The incident came just five days before President Trump met with North Korean leader Kim Jong Un in Hanoi.

The Associated Press contributed to this report.