Death toll of Halloween stampede in Seoul rises to 154, including 4 Chinese

South Korean President Yoon Suk-yeol on Sunday announced a period of national mourning over the tragedy.

"This is truly horrific," he said in a televised national address. "The government will designate the period from today until the incident is brought under control as a national mourning period and will place top priority on administrative affairs in recovery and follow-up measures."

He also expressed condolences over the deaths and wished a speedy recovery for the injured.

Immediately after the address, Yoon visited the scene in Itaewon.