The Japanese city of Hiroshima marks today the 77th anniversary of the world's first atomic bomb attack.
On the occasion of the anniversary of the attack on Hiroshima, UN Secretary General Antonio Guterres and other officials are on the alert for a new explosion of weapons and bombs, after the entry of the Russian army into Ukraine.
Russia invaded Ukraine on February 24, and shortly thereafter, Vladimir Putin raised the possibility of a nuclear attack.
Because of the hostilities, concern about the safety of Ukraine's nuclear power plants has also intensified.
Thousands of people filled Hiroshima's 'Peace Park' to commemorate the 140,000 victims of the bombing shortly before the end of World War II.
This is the second time that the UN secretary general participated in the anniversary events.
"Nuclear weapons are meaningless. They do not guarantee any security, only death and destruction," Guterres stressed. After three quarters of a century, we must ask ourselves what we learned from the mushroom that rose in the sky of this city in 1945", he added.
Antonio Guterres avoided direct reference to Russia, which calls the invasion of Ukraine a "special military operation".
Hiroshima Mayor Kazumi Matsui, who this year did not invite the Russian ambassador to Japan to the event, was tougher in his speech and criticized the military attack on Ukraine.
"By invading Ukraine, the Russian president, who was elected to protect the lives and property of his citizens, is using them as instruments of war, taking the lives and livelihoods of civilians in another country," Matsui said.
About 140,000 people were killed when the United States dropped a single atomic bomb on Hiroshima in the early morning hours of August 6, 1945.
Three days later, the second atomic bomb is dropped on the city of Nagasaki, killing 70,000 people.
As a result, Japan surrendered on August 15.