The US forces dropped plague-infected fleas on North Korea in March 1952, according to report on germ warfare released online.
The report published in February 2018 mentioned one episode of the dropping of plague-infected human fleas on a single small village.
In it mentioned in the report that Pak Yun-Ho, a 26 year old peasant born and raised in the village was woken up by what he and later others identified as an American plane that had been circling above the village around 4:00am.
“The enemy plane flew away after circling several times without strafing or bombing. I couldn’t sleep again after this,” Pak told local investigators then. “Song Chang-Won and I thought that these numerous fleas floating on the surface of water must have been dropped by the American plane circling over our village before dawn. We, therefore, immediately informed the chairman of the Village People’s Committee of this incident,” Pak told interviewers
In September 1952, the International Scientific Commission for the Investigation of the Facts Concerning Bacterial Warfare in Korea and China (ISC) issued a report finding that the US had conducted biological warfare during the Korean War.