As of Wednesday, it has been 18 days since North Korean leader Kim Jong Un was seen publicly. The despotic ruler vanished from the pubic eye after a government meeting on April 11 and since then has been dogged by rumors of heart problems and, potentially, his death.

After being notably silent on the leader’s activities or whereabouts, North Korea’s state-run media outlets have recently released a series of letters as proof that Kim is still alive. These letters, signed in Kim’s name but of dubious authenticity, were addressed to leaders in Cuba, South Africa, and Syria, with another sent to workers on a tourism project in the resort town of Wonsan thanking them for their service.

Kim has been rumored to be staying Wonsan, where his family owns a summer home. North Korean media has not released any evidence of Kim in Wonsan.

Despite these assertions from the state and assurances from the South Korean government that he is “alive and well,” Kim has yet to make any sort of public appearance. The U.S. government, which continues to monitor the situation, has not been able to confirm his healthy or whereabouts.

Concern first began to escalate when Kim failed to appear for the Day of the Sun, a major North Korean holiday celebrating the birthday of his grandfather, Kim Il Sung. Experts have called such an absence close to “blasphemy” in the secretive country.

However, South Korean officials have contradicted this theory, pointing out that numerous public events in North Korea have been canceled due to the outbreak of coronavirus. Under those circumstances, they argue, it would not be strange for Kim to stay in seclusion to avoid catching the virus.

Early on, rumors spread that Kim was either dead or in a vegetative state following a botched heart operation. Reports of the leader’s passing came mostly from unreliable outlets in China and Japan, with more reputable news sources unable to confirm his condition. All that could be confirmed was that several Chinese medical professionals had traveled to North Korea to check on Kim’s health.

The health of Kim Jong Un, pictured center in an image released on April 12, 2020, is frequently the subject of speculation, but little concrete is known about the secretive leader
The health of Kim Jong Un, pictured center in an image released on April 12, 2020, is frequently the subject of speculation, but little concrete is known about the secretive leader KCNA VIA KNS / STR