Yet another Defense Security Command official has been caught passing on classified documents, raising serious concerns about the organization’s function as the military counterintelligence agency and protector of military secrets.

On Friday, the military said a Navy lieutenant commander was arrested early last month on suspicion of leaking classified military secrets to a Chinese national. According to the military, the officer is suspected of having handed over military information to a Chinese national whom he had met in China while studying there from 2009-2012. The Chinese student was an agent. The officer is suspected of having received several thousand dollars in exchange for the documents.

It is said that the Navy officer was arrested at an airport as he was departing for China to assume a posting at the Korean Embassy in Beijing. While initial reports said that the documents the officer passed on included information on the Terminal High Altitude Area Defense battery, the military has since denied that the leaked documents included such material. Nevertheless, it is not difficult to imagine that much more classified information could have gone over to the Chinese had the officer gone on to assume his post at the Beijing Embassy as an aide to the military attache.

The Navy officer is just the latest in a number of recent arrests of Defense Security Command employees. In May, two DSC employees were caught supplying some 30,000 magazines to a Lebanese arms smuggler for 360 million won, disguising them as oil filters. In April, two DSC employees were arrested on charges of handing over military secrets to a major arms dealer. The two leaked 141 documents and received a total of 10 million won in exchange on 20 occasions. That works out as classified information being sold at 70,000 won a piece.

An urgent reform of the DSC is in order. How long can the country afford to have its classified documents compromised by the very people put in charge of their safekeeping?