This is despite Pyongyang insisting it will retaliate to such actions, which have been cited as a cause for a breakdown in the relations between the two Koreas. North Korea cut a hotline with Seoul and blew up a joint liaison office. Mr Park said in a statement the leafleting was for “a struggle for justice for the sake of liberation of” North Koreans.
Local officials in South Korea are looking into the remarks.
They may call for an investigation as a potential safety threat for people who live near the border.
Mr Park referred to North Korean Supreme Leader Kim Jong-un as “an evil” and described his rule as “barbarism”.
He asked: “Though North Korean residents have become modern-day slaves with no basic rights, don’t they have the rights to know the truth?”
Mr Park has accused Seoul of sympathising with North Korea or caving into its threats.
An administrative order has been placed forbidding people from certain border areas from flying leaflets across the 38th parallel.
Anyone guilty of this faces up to a year in prison and a fine of ₩10m (£6,647.32).
North Korea does not tolerate outside criticism of the Kim family, who have governed the nation since its foundation.
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Mintaro Oba, a former State Department official added: “It’s clear there is a serious effort underway to raise the domestic stature of Kim Yo Jong. The latest statements and actions she has taken aim to portray her at home as someone who is strong, decisive, and capable of leadership in her own right.”
State media from inside North Korea has, however, said the nation has suspended plans for military action against the South.
State media saw the decision was taken at a meeting chaired by Kim.
The Central Military Commission was said to have reached the decision after considering the “prevailing situation”.
Yonhap, a South Korean news agency, says the North has also begun to dismantle loudspeakers erected to transmit loud anti-South messages across the border.
According to the Korean Central News Agency, there was also discussion on measures to “further bolstering the war deterrent of the country.”
The sudden breakdown of relations even saw the resignation of Kim Yeon-chul, Seoul’s unification minister.
Mr Kim resigned on Wednesday.
President Moon Jae-in accepted the resignation on Friday.