President Moon Jae-in on Thursday mourned the victims of a warehouse fire that left at least 38 people dead and 10 others injured the previous day, saying the disaster has added woes to the coronavirus crisis.

"Many people were killed. It is so sad that this unfortunate accident has happened when everybody is working hard to overcome COVID-19," Moon said in a message marking Buddha's Birthday. "I deeply mourn the victims and wish those injured a quick recovery."

South Koreans observed the Vesak holiday with a solemn mood rather than celebrations this year amid the monthslong fight against COVID-19 and Wednesday's warehouse fire in Icheon, 50 kilometers southeast of Seoul, one of the deadliest blazes in years.

"When our neighbor is in pain, we are in pain too," Moon said on his social media account. "I feel so sorry and a sense of heavier responsibility for the unfortunate incident that occurred in the midst of national efforts to overcome COVID-19."

He expressed his condolences to the victims and wished the injured a quick recovery.

The president pointed out that Buddhism has played a role traditionally in uniting people at a time of national crisis in South Korea.

Buddhist followers have helped those in need through donations and sharing, he added.

"The warm heart of the Buddhist community has been always of help to the people," Moon said. "Mercy, which regards the pain of the neighbor as mine, is our strength and hope."

Moon reaffirmed the top priority of protecting the lives and safety of the people on the occasion of Vesak Day. (Yonhap)