South Korea police probing US ambassador attacker's visits to North Korea

South Korean police said on Friday they are investigating possible links between a knife attack on the US ambassador to Seoul and the assailant's frequent visits to North Korea, as they also sought to charge him with attempted murder.

US ambassador Mark Lippert needed 80 stitches after his face was slashed at a forum discussing Korean unification in the capital, Seoul, on Thursday.
 
The attack was carried out by a Korean nationalist who said he was protesting against annual US-South Korean military exercises that began this week.
 
A senior official in the team investigating the attack said police have requested a formal detention warrant on charges that include attempted murder against the assailant, identified as 55-year old Kim Ki-jong.
 
Investigators have established that Kim made seven visits to North Korea between 1999 and 2007.
 
"We are investigating whether there is any connection between the suspect's visits to North Korea and the crime committed against the US ambassador," Yoon Myeong-seong, chief of police in Seoul's central Jongno district, told reporters.
 
Most South Koreans never have visited the secretive North.
 
The two states technically remain at war under a truce that ended the 1950-53 Korea War, and a heavily armed border divides the peninsula.
 
According to South Korea's Unification Ministry, Kim planted trees near the city of Kaesong, just across the border, during his visits to North Korea.
 
Kim also faces charges for assaulting a foreign envoy and obstructing business operations.                        
Police raided his home and office early on Friday, looking for evidence of whether he also broke a state security law that bans supporting the regime in Pyongyang.
 
Police have also identified Kim as a member of the pro-unification group that hosted the forum.
 
North Korean state media has said the attack against Lippert was "deserved punishment" for the military drills, calling the assault "the knife of justice".
 
South Korea's Unification Ministry condemned the statement, calling it "senseless".
 
The South Korean government ordered increased security for diplomatic missions, including the US embassy, and police said on Friday they were providing protection for Lippert.
 
Lippert was accompanied by a bodyguard when the attack took place on Thursday. Police were also present, although not at the request of the US embassy or organisers.
 
The United States is South Korea's closest ally and maintains a military presence that includes 28,500 personnel.
 
That has drawn protest and criticism from some in South Korea in the past but public opposition has eased in recent years.
 
Lippert is recovering in a Seoul hospital and has said he is in "good spirits".
 
Doctors at Yonsei University's Severance Hospital said on Friday Lippert was likely to remain there until early next week, when they plan to remove his stitches.
 
Lippert underwent surgery on Thursday for an 11-cm (4 inches) gash on the right side of his face and a puncture wound on his left wrist that caused nerve damage, which was repaired.