A man stabbed three people to death in Seoul on Wednesday at a pizza restaurant, police said — a rare attack in the normally safe South Korean capital.

The attack in Seoul's Gwanak district was carried out by the restaurant's owner, who became embroiled in a dispute with contractors before stabbing three people and then attempting to harm himself, police said.

Police said in a statement they had responded at around 11:00 a.m. to a call that said: "Help me, I've been stabbed."

The victims — two men and one women — were taken to hospital but pronounced dead.

The suspect, who is in his forties, "attempted to take his own life" at the scene but was stopped, according to the statement by police, who said they plan to take him into custody depending on the medical treatment he requires.

South Korea is generally a very safe country, with a murder rate of 1.3 per 100,000 people in 2021, according to official statistics, well below the global average of around six per 100,000.

But recently a number of stabbing cases have occurred, including one involving a man who stabbed three police officers in May.