A grandson of ex-U.S. President Harry Truman, who ordered the atomic bombings of Japan during World War II, is in Hiroshima to attend a memorial service for the victims.

Clifton Truman Daniel visited the Hiroshima Peace Memorial Park on Saturday and laid a wreath for the 140,000 people killed by the Aug. 6, 1945, bombing authorized by his grandfather. Another atomic blast in Nagasaki three days later killed 70,000 more.

"I think this cenotaph says it all -- to honor the dead to not forget and to make sure that we never let this happen again," Daniel said after offering a silent prayer.

Daniel, 55, is in Japan to attend ceremonies next week in Hiroshima and Nagasaki marking the 67th anniversary of the bombings. His visit, the first by a member of the Truman family, is sponsored by the peace group Sadako Legacy, named after Sadako Sasaki, an A-bomb victim who died of leukemia at age 12. While in the hospital, Sadako folded hundreds of paper cranes after hearing a legend that people who make 1,000 origami cranes can be granted a wish.