Seoul, Oct 14 (IANS): Kim Yo-jong, the influential sister of North Korean leader Kim Jong-un, accused the South Korean military on Monday of sending unmanned drones carrying leaflets over Pyongyang in recent days.

"We clearly know that the main culprit behind the Pyongyang drone incident is the trash of the South Korean military," Kim said in a statement, Yonhap news agency reported quoting North Korea's state-run Korean Central News Agency.

On Friday, North Korea's Foreign Ministry claimed that South Korean drones carrying anti-North Korean leaflets were detected over Pyongyang on October 3, as well as on Wednesday and Thursday last week, and warned of retaliation if the flights continued.

South Korean Defence Minister Kim Yong-hyun said he could not confirm the North's allegations. Kim Yo-jong provided no evidence to support her claim. She used harsh language to criticise both South Korea and the United States for the drone flights.

Likening South Korea to "mongrel dogs" and the US to their "master," she asserted that the ultimate responsibility for the alleged actions of "dogs" lies with their "master."

Her statement came a day after the South Korean Defence Ministry condemned the North for making threats of force and warning of a "terrible catastrophe" over drone incidents without even confirming the source of the flights.

Kim earlier suggested that South Korean activist groups might be behind the drone flights, criticising the South Korean military for failing to properly monitor such activity.

"If the military failed to properly identify civilian organisations' drones freely crossing the border, it is clearly a problem," she said in a statement Saturday.