LOS ANGELES (Reuters) - A former U.S. Marine accused of stealing electronics from the North Korean embassy in Madrid in a robbery of the diplomatic compound was ordered by a federal judge in Los Angeles on Tuesday to remain in U.S. custody pending possible extradition to Spain.

A combination photo of former U.S. Marine Christopher Philip Ahn allegedly shown in a still photo from a surveillance camera standing in front of and entering the North Koria embassy in Madrid, Spain, February 22, 2019. U.S. Attorney's Office Central District of California/Handout via REUTERS

The judge also ordered the unsealing of U.S. court documents in the case against Christopher Philip Ahn, 38, who was arrested by federal agents in Los Angeles on Thursday.

Spanish authorities have sought Ahn’s extradition from the United States. He is charged there with being among a group of seven intruders who stormed the North Korean mission on Feb. 22, restrained and physically beat some embassy personnel, held them hostage for hours and then fled.

Spanish investigators identified the intruders as self-professed members of a group that calls itself Cheollima Civil Defense and seeks the overthrow of North Korean leader Kim Jong Un. According to U.S. court documents, the raiders removed computers, computer drives and a mobile phone from the embassy before the alleged ringleader, Adrian Hong, traveled to the United States and met with the FBI.

Hong, a Mexican citizen and U.S. resident, was an activist who co-founded the non-profit human rights group Liberty in North Korea but later left that organization. His whereabouts remain unknown.

The anti-Kim group, which also calls itself Free Joseon, has denied attacking the embassy, insisting its members were invited inside.

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RAID COINCIDED WITH SUMMIT

Ahn is charged in Spain with breaking and entering, illegal restraint, making threats, robbery with violence and intimidation, causing injuries and criminal organization, U.S. court documents say. He could face more than 10 years in prison if convicted there.

The incident at the embassy came at a sensitive time, just days ahead of a second summit between U.S. President Donald Trump and Kim that abruptly collapsed without the two leaders reaching a deal on North Korea’s nuclear weapons program.

North Korea’s foreign ministry denounced the incident as a “grave terrorist attack” and cited rumors that the FBI was partially behind the raid. The U.S. State Department has said Washington had nothing to do with it.

Ahn arrived in Madrid on the morning on Feb. 22 and left shortly after the raid, Assistant U.S. Attorney John Lulejian told the judge on Tuesday. He was photographed outside the embassy wearing black and carrying a backpack that may have contained weapons, Lulejian said.

The FBI received the stolen material and returned it to the Spanish court investigating the raid, and Spanish authorities have returned the items to Pyongyang’s mission, according to a Spanish judicial source.

In U.S. court on Tuesday, Ahn’s public defender, Callie Steele, asked Magistrate Judge Jean Rosenbluth to keep records in the case sealed to protect her client, saying North Korea’s leader had ordered assassinations in the past and that credible death threats had been made against Ahn.

She also asked that Ahn be placed under home detention so he could care for his ill mother and blind grandmother at their house in Chino, California. The judge denied the request, ordering he remain in federal custody ahead of his next court appearance, set for July 18.

Ahn was arrested at Hong’s apartment in Los Angeles last week while dropping something off there, Steele told the judge.

He was armed at the time with a handgun, which he legally owned to protect himself, after the FBI informed him of threats on his life, she said in court.

Ahn was born and raised in Southern California and later obtained a masters degree in business administration from the University of Virginia, Steele said. He was honorably discharged after service in the U.S. military, she said.