North Korean leader Kim Jong Un sent a condolence letter to South Korean President Moon Jae-in Wednesday following the passing of his mother the previous day, Seoul’s Blue House said Thursday.

The letter was delivered through Panmunjom at the inter-Korean border on Wednesday, according to Blue House spokesperson Ko Min-jung, though she did not specify who from the North delivered it.

President Moon’s mother Kang Han-ok passed away in the southern city of Busan on Tuesday evening. A funeral mass was held there Thursday with Moon in attendance.

Kim Jong Un “expressed his deep sympathies honoring the memory of Madam