A drunken man attacked three men with a knife early Tuesday morning after an argument over the safety of U.S. beef, Yonhap News reported quoting police sources.

The victims, all in their 30s, were taken to a hospital but their injuries are not life-threatening, according to police.

The assailant, identified only by his family name Park, argued that U.S. beef is safe for consumption before assaulting the men just outside the Jogye Temple, headquarters of the country's largest Buddhist sect.

The victims are members of the Anti-Lee Myung-bak Cafe, an online community supporting organizers of the anti-U.S. beef protests who have been taking refuge since July in the Buddhist temple to evade arrest.

"A man approached arguing that Korean beef is more dangerous than U.S. beef, and then appeared to leave before coming back with a knife," a witness was quoted as saying.

Police said the suspect runs a restaurant near the temple and plan to seek an arrest warrant for Park on charges of attempted murder.