Fifteen years ago North Korean founder Kim Il-sung died under mysterious circumstances and judging by how his son Kim Jong-il looks today, he may not be far behind joining his dad:

A thin-looking Kim Jong Il made a rare public appearance Wednesday as North Korea paid solemn respects to his father, the country’s late founder, on the 15th anniversary of his death.

The memorial was the second major state event that the 67-year-old Kim has attended in person since reportedly suffering a stroke last summer. In early April, he presided over a parliamentary meeting where he was re-elected as leader.

Footage from broadcaster APTN showed Kim dressed in a khaki suit, looking more gaunt and with less hair than in April. As in April, he limped slightly while walking into the packed Pyongyang auditorium in what is believed to be an effect from the stroke.

Kim bowed his head during a moment of silence. A portrait of a giant red flag with an image of his father, a smiling Kim Il Sung, dominated the backdrop.

Kim’s health has sparked concerns about instability and a power struggle if he were to die without naming a successor. His third and youngest son, Kim Jong Un, has widely been reported as being groomed as heir, but the regime has made no announcement to the outside world.

Wednesday’s memorial came after the North conducted a number of banned ballistic missile tests last weekend, fueling tensions already running high after Pyongyang‘s second nuclear test on May 25 led to punishing U.N. sanctions.

The regime used the memorial to criticize the United States and South Korea.

“We will sternly smash the U.S. imperialist forces and South Korea’s puppet regime anti-unification plot,” Kim Yong Nam, the North’s No. 2 leader, told the ceremony, according to footage broadcast on state television.

“We will achieve the historical mission of national unification by realizing” Kim Il Sung and Kim Jong Il’s policies for that, he added.

Kim Il Sung died of heart failure on July 8, 1994 at the age of 82. He ran the communist country with an iron grip and was the object of an intense personality cult.  [Associated Press]