By Benjamin Kang Lim and James Pearson
BEIJING/SEOUL (Reuters) - North Korean leader Kim Jong Un is in firm control of his government but hurt his leg taking part in a military drill, a source with access to the secretive North's leadership said, playing down speculation over the 31-year-old's health and grip on power in the nuclear-capable nation.
North Korea's state media, which usually chronicle Kim's activities in great detail, have not mentioned any public appearances since he attended a concert with his wife on Sept. 3 and the official KCNA news agency indicated he did not attend an important political anniversary on Friday.
In the previous two years, Kim marked the anniversary of the founding of North Korea's Workers' Party with a post-midnight visit to the Pyongyang mausoleum where the bodies of his father and grandfather are interred.
But the report by KCNA did not mention Kim's name in a list of high-level party and military officials who attended an event at the mausoleum on Friday. A flower basket from Kim was placed at the mausoleum, it said.
The source with access to the North's leadership, who has close ties to Pyongyang and Beijing, said on Thursday that Kim had hurt his leg while inspecting military exercises.
"He ordered all the generals to take part in drills and he took part too. They were crawling and running and rolling around, and he pulled a tendon," the source told Reuters on condition of anonymity.
"He injured his ankle and knee around late August or early September while drilling because he is overweight. He limped around in the beginning but the injury worsened," the source said.
Kim, who has rapidly gained weight since coming to power after his father died of a heart attack in 2011, had been seen walking with a limp since an event with important officials in July, which would imply he may have aggravated an earlier injury.
Kim needs about 100 days to recuperate, said the source, whose information could not be independently verified.
"Kim Jong Un is in total control," said the source.
Kim's absence from public view is fuelling speculation over the state of his health and whether he may have been sidelined in a power struggle.
"The longer he remains out of the public eye, the more uncertainty about him, and the status of his regime, will grow," said Curtis Melvin, a researcher at the U.S.-Korea Institute at the Johns Hopkins School of Advanced International Studies in Washington.
NOT KIM'S FIRST ABSENCE
On Friday, South Korea's Unification Ministry said it believes Kim remains in charge, citing a message conveyed by him via a delegation visiting last weekend, and Pyongyang's continued public position that Kim leads the country.
"So it appears it is being normally ruled by Kim Jong Un," ministry spokesman Lim Byeong-cheol said.
Patrick Ventrell, a spokesman for the U.S. National Security Council, said the United States monitored events in North Korea extremely closely and had seen the reports about Kim Jong Un’s health, but played down speculation about upheaval in the country.
"Given that the (North Korean) regime is the most opaque on earth, it’s not surprising that there is very little reliable and publicly available information about this. Regarding rumors of a coup, as we have said previously, those appear to be false," he said.
North Korean officials have denied that Kim's public absence since early September is health-related and a U.S. official following North Korea said this week there were no indications he was seriously ill or in political trouble.
It remains unclear why a leg injury would keep Kim out of the public eye for so long, although this is not the first time he has been missing from view.
In June 2012, six months after coming to power, state media failed to report on or photograph him for 23 days.
Kim re-appeared the next month when he was reported attending a show at a dolphinarium.
Speculation that Kim's unusually long absence from public view may be due to ill health was fueled by a North Korean television report late last month that said he was suffering from "discomfort".
Some North Korea watchers also suggest that Kim may have been sidelined in a power struggle, a scenario they say was reinforced by the unexpected visit on Saturday of a high-level delegation to the closing ceremony of the Asian Games in Incheon, South Korea.
Another interpretation of that visit holds that it was meant to convey stability in Pyongyang.
The source with knowledge of Kim Jong Un's health said rumors of a coup were "rubbish".
"It would have to be a very subtle coup indeed not to disrupt international travel plans," said Andray Abrahamian of the Choson Exchange, a Singapore-based group running a program for North Koreans in Southeast Asia.
North Korea is a hereditary dictatorship centered on the ruling Kim family. Kim's sister, Kim Yo Jong, is known to have an official role within the ruling party. His brother, Kim Jong Chol, and his estranged half-brother are not in the public eye.
Kim was absent from a Sept. 25 meeting of the Supreme People's Assembly, or parliament, the first he has not attended since coming to power three years ago.
Abrahamian said it was unlikely Kim had been usurped.
"Kim Jong Un has always shared power with other key figures and even if the internal balance of power has shifted, it is unlikely that they would want to remove him, given his unmatchable symbolic value. Again, though, everyone is guessing," he said.
(Additional reporting by Ju-min Park in Seoul and Jeff Mason and David Brunnstrom in Washington; Writing by Tony Munroe; Editing by Raju Gopalakrishnan and Chizu Nomiyama)