The US ambassador to South Korea, Mark Lippert, was on Thursday slashed in the face by a Korean nationalist, during a public event at an arts centre in Seoul.
Lippert, 42, was assaulted during a breakfast conference as he was preparing to give a lecture about prospects for peace on the divided Korean Peninsula.
The ambassador was bleeding from wounds to his face and wrist, but was able to walk after the attack.
The US embassy said Lippert was in stable condition after surgery at a Seoul hospital. Hours after the attack Lippert tweeted that he was “Doing well and in great spirits”.
The assailant, identified by police as Kim Ki-jong, 55 was immediately arrested at the scene.
Police said Kim had tried to attack the then Japanese ambassador to Seoul by hurling a piece of concrete and was given a suspended jail term in 2010.
A District Police Chief, Yoon Myung-soon, said “We have detained him and are investigating the cause of the attack and other circumstances”.
Witnesses and police said Kim used a small fruit knife in the attack, which took place inside a large government arts center across the street from the heavily guarded U.S. embassy on the South Korean capital’s main ceremonial thoroughfare.
According to a witness, he repeatedly shouted “No drills for war.” He was apparently referring to the ongoing large-scale South Korea-US military exercise, which occurs every year about this time.
“We strongly condemn this act of violence,” U.S. State Department spokeswoman Marie Harf said.
A White House official said the US President, Barack Obama, had also called Lippert to wish him a speedy recovery.
Kim was dressed in traditional Korean clothing and shouted that North and South Korea should be reunited just before he attacked Lippert.
He is said to be the head of a relatively small civic organisation that has been calling for peace and reconciliation with North Korea.