PYONGYANG, DPRK -Smiling and saluting, new leader Kim Jong-un reviewed a parade of thousands of soldiers on Thursday who vowed to protect him with their lives as the Democratic People's Republic of Korea commemorated the 70th birthday of his late father, Kim Jong-il. 

Kim Jong-un, wearing a dark suit and a solemn expression, bowed deeply before a large portrait of his smiling father in Kumsusan Memorial Palace in Pyongyang. Hundreds of senior officials, military leaders and citizens followed to pay their respects. 

Outside the palace, a huge crowd of DPRK soldiers lined up in neat rows, listening to speeches praising the Kim family. Later, the new leader and other officials watched as goose-stepping soldiers marched by, followed by military jeeps and trucks carrying artillery guns and rocket launchers. Fireworks exploded and military music boomed. 

Steadfast devotion 

Battles can break out without warning, Military General Staff Chief Ri Yong-ho told the televised ceremony, vowing to "wipe out US imperialists and Republic of Korea puppet traitors" and reunify the peninsula in case of war. 

"Kim Jong-un! Protect him with all our might!" roared thousands of troops from the army, navy and air force, state television showed. 

The event was the latest in a series designed to bolster loyalty to Kim Jong-un, after Kim Jong-il died suddenly on Dec 17 at age 69 and was succeeded by his son. 

The parade outside Pyongyang's Kumsusan Memorial Palace marked the changing of its name to the Kumsusan Palace of the Sun, a TV announcer said, in a tribute to the late leader and to his own father and founding president Kim Il-sung. 

Just beforehand, hundreds of top military and civilian officials paid tribute inside the marble-pillared palace to Kim Jong-il. 

Since Kim's death two months ago, expressions of mourning and adoration have been common in Pyongyang. 

Soldiers in large-brim caps saluted a smiling portrait. Civilians bowed deeply before the image as solemn music played. 

Kim Jong-un led the commemoration inside Kumsusan, where his father's embalmed body will lie in state. Kim Il-sung's body is already on display there. 

Their voices throbbing with emotion, TV commentators said "father General" Kim Jong-il had "brought proud victory and glory to the country". 

"There will be only victory and glory in the future of the DPRK ... led by the respected leader Kim Jong-un," a commentator predicted.