North Korea marks 2 years since death of Kim Jong Il

North Koreans take flowers to the North Korean Consulate in the Chinese border town of Dandong to pay their respects on the second anniversary of the death of former leader Kim Jong Il, on December 17, 2013.

North Korean leader Kim Jong Un presided over a mass gathering of military and party officials Tuesday that was broadcast live on state television at a time of growing concern over the stability of his hardline regime.

The ceremony in central Pyongyang, marking the second death anniversary of Kim's father and former leader Kim Jong Il, included a number of speeches that stressed unquestioning loyalty to the young supremo and included a stark warning to rival South Korea.

It followed the shock execution last week of Kim Jong Un's uncle and one-time political mentor, Jang Song Thaek.

The purge raised questions about factional infighting at the top of the North Korean hierarchy and prompted both Seoul and Washington to warn of possible provocative acts by the nuclear-armed regime.

State television showed the massed ranks of tens of thousands of military and party officials sitting stony-faced in pin-drop silence for several minutes, before rising to greet Kim Jong Un with thunderous applause as he arrived to take his place on the leadership podium.

"We should be warriors to safeguard the party centre with our lives ... with the conviction that we know no one but the great comrade Kim Jong Un," North Korea's ceremonial head of state, Kim Yong Nam, said in an opening address.

He added that the country had made "great strides" in the two years since Kim took over the reins of power after his father's death.

Under Kim's leadership, North Korea has successfully placed a satellite in orbit and in February this year conducted its third — and most powerful — nuclear test.

"By holding the respected comrade Kim Jong Un in high esteem ... our country will prosper as the country of eternal sun," Kim Yong Nam said.

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Tuesday's mass meeting also heard a keynote address by top military leader Choe Ryong Hae — who some analysts believe had a hand in the ouster and execution of Jang Song Thaek.

"Our revolutionary forces know ... no one but comrade Kim Jong Un," said Choe, a close Kim Jong Un confidant who holds the military rank of vice marshal and is director of the Korean People's Army's General Political Department

The military will support "our supreme commander, under any storms and hardships," said Choe, who also fired off a warning at rival South Korea.

"If the enemies drop a single drop of fire on our motherland, our soldiers will immediately storm out to wipe out all the invaders and achieve unification," he said.

At a meeting of top defence and national security officials on Monday, South Korean President Park Geun Hye had warned that the recent leadership shake-up in the North could presage some aggressive behaviour from Pyongyang.

"We can't rule out the possibility of contingencies such as reckless provocations," Park said, urging the military to step up vigilance along the heavily fortified border.

More from GlobalPost: Kim Jong Un's executed uncle 'had been plotting a coup since mid-1990s'

There was no sign on the leadership podium of Kim Jong Un's aunt and Jang's widow, Kim Kyong Hui — a major political player in her own right who holds the military rank of four-star general.

She had been named by state media at the weekend as attending an official function, suggesting she may have survived the purge of Jang associates.

Tuesday's meeting came the day after a massive military rally in Pyongyang, during which Choe also spoke, urging troops to protect Kim Jong Un "at the cost of their lives."

Jang's execution — just days after he was ousted from all his party and military positions — marked the biggest political upheaval since the younger Kim inherited power.

The purge was staged in an extraordinarily public and dramatic manner, with Pyongyang releasing images of Jang being dragged out of a party meeting.

Jang had been seen as Kim's political mentor but the 67-year-old's growing political influence and power was increasingly resented by the young leader, analysts said.

Since the execution, state media has shown Kim making a series of public appearances around the country in a move apparently intended to show he is firmly in charge.