HIROSHIMA, Japan, Aug. 6 (Xinhua) -- Hiroshima, a Japanese city hit by a U.S. atomic bomb at the end of World War II, marked the 74th anniversary of the bombing on Tuesday.

An annual memorial ceremony, held at the Peace Memorial Park near Ground Zero, was attended by about 50,000 audiences paying respect, including representatives from about 90 countries.

Japanese Prime Minister Shinzo Abe delivered a speech during the ceremony, stressing the importance of continuing efforts to realize "a world free of nuclear weapons."

As the only country that has experienced atomic bombings in war, Japan's duty to eliminate nuclear weapons remains unchanged even in the Reiwa era, Abe said.

A uranium-core atomic bomb named "Little Boy," dropped onto Hiroshima in western Japan by a U.S. bomber, exploded above the city at 8:15 a.m. local time on Aug. 6, 1945, killing an estimated 140,000 people by the end of the same year.

Nagasaki was also hit by an atomic bomb on Aug. 9, 1945, prompting Japan's surrender and the end of World War II.