South Korea’s main opposition party leader, Lee Jae-myung was stabbed in the neck by a man, during his visit to the southern city of Busan on Tuesday.

The party officials said the attack was bloodied but he was conscious, when he was on tour to the construction site of the Gadeokdo New Airport, CNN reported.

Lee was stabbed while he was talking to journalists leaving him with a 1-centimeter laceration on the left side of his neck, Democratic Party spokesperson Kwon Chil-seung said.

He suffered “suspected damage to his jugular vein” and doctors were concerned he may have additional bleeding, Kwon said, citing doctors.

“He will quickly undergo a surgery” at the Seoul National University Hospital, after having been transferred there from Busan, the spokesperson said, describing the attempt on Lee’s life as an act of “terrorism” and “a serious threat to democracy.”

Earlier in the day Democratic Party’s floor leader Hong Ik-pyo said Lee was “in a conscious state” in hospital.

The assailant, who was arrested at the scene, is a man in his sixties, according to Busan police. He approached Lee for an autograph before carrying out the attack with an 18 cm (7 inch) long knife purchased online, the police said in a briefing.

Footage of the brazen attack, captured on live television at the press conference, showed an unidentified man at the front of the crowd suddenly lunging at Lee and striking him in the neck, sending Lee collapsing backwards.

The attacker was then wrestled to the ground and restrained by several people.