SEOUL, South Korea – South Korea’s spy agency believes it has solved the mystery of North Korean leader Kim Jong Un’s 6-week public absence that set off a frenzy of global speculation, a lawmaker who attended the agency’s closed-door briefing said today.

The National Intelligence Service told legislators Tuesday that a foreign doctor operated on Kim in September or October to remove a cyst from his left ankle, lawmaker Shin Kyung-min said. He said the spy agency also told lawmakers that the cyst could recur because of Kim’s obesity, smoking and heavy public schedule.

After last being seen in state media on Sept. 3, Kim reappeared on Oct. 14 hobbling with a cane, but smiling and looking thinner. The speculation during his absence was particularly intense because of the Kim family’s importance to the country locked in a long-running international standoff over its nuclear and missile programs.

Shin said the spy agency identified Kim’s condition as tarsal tunnel syndrome, an often painful condition that is caused by the compression of a nerve, sometimes because of a cyst.