North Korea has celebrated the 80th birthday of late leader Kim Jong Il with a concert, fireworks and a rare outdoor ceremony near its border with China, state media reported.

His son – and current leader – Kim Jong Un attended a state ceremony at Samjiyon city on Tuesday, on the eve of the birthday, the official Korean Central News Agency reported.

When Kim Jong Un appeared, all the participants “burst into stormy cheers” before he paid tribute to the statue of his father, KCNA said.

The event showed participants’ resolve to rally behind Kim Jong Un and achieve prosperity with self-reliance, KCNA said, and similar ceremonies were held across North Korea to mark the anniversary.

KCNA said senior officials visiting Samjiyon city observed fireworks and a concert.

It is rare for North Korea to hold a high-profile state event in the city at the foot of Mount Paektu, the highest peak on the Korean peninsula which is the heart of North Korea’s foundation myth revolving around the Kim family.

A major development project has also been under way in Samjiyon, which Kim Jong Un has said epitomises his country’s “iron will” to achieve prosperity.

The birthday of Kim Jong Il is one of the most important holidays in North Korea, along with that of Kim Il Sung, the late grandfather of Kim Jong Un who established North Korea in 1948.

Kim Jong Un has ruled North Korea since Kim Jong Il died of a heart attack in late 2011.

On Wednesday, North Koreans climbed Pyongyang’s Mansu Hill to lay bouquets of flowers and to bow before the giant statues of Kim Jong Il and Kim Il Sung.

Elsewhere in the capital, signs with celebratory messages like “the great event of the nation” were set up along streets.

Last month, Pyongyang conducted a spate of missile tests in what some experts say were an attempt to pressure the US to offer concessions like sanctions relief.

North Korea admitted it has faced severe economic difficulties due to the Covid-19 pandemic.

Pyongyang paused testing earlier this month before the start of the Winter Olympics in China, its last major ally and economic pipeline.